This IELTS Reading post focuses on all the solutions for IELTS Cambridge 8 Test 4 Reading Passage 2, which is entitled ‘Biological control of pests’. This is an aimed post for IELTS candidates who have great problems in finding answers for the Academic Reading module. This post can guide you the best to comprehend each Reading answer without facing much difficulty. Tracing IELTS Reading answers is a gradual process, and I sincerely hope this post can help you in your IELTS Reading preparation.

IELTS Cambridge 8 Test 4: AC Reading Module

Reading Passage 2:

The headline of the passage: Biological control of pests 

Questions 14-17: Multiple choice questions

[This type of question asks you to choose a suitable answer from the options using the knowledge you gained from the passage. Generally, this question is found as the last question so you should not worry much about it. Finding all the answers to previous questions gives you a good idea about the title.]

Question 14: The use of pesticides has contributed to –

Keywords for this question: use of pesticides, contributed to,    

In paragraph no. 1, the writer says in lines 2-4, “.. .  Apart from engendering widespread ecological disorders, pesticides have contributed to the emergence of a new breed of chemical-resistant, highly lethal superbugs. .”

Here, around the world = widespread, imbalance = disorders,

So, the answer is: B (an imbalance in many ecologies around the world.)

 

Question 15: The Food and Agriculture Organisation has counted more than 300 agricultural pests which –

Keywords for this question: The Food and Agriculture Organisation, counted, more than 300, agricultural pests,    

In paragraph no. 2, lines 1-2, the writer says, “According to a recent study by the Food and Agriculture Organisation (FAO), more than 300 species of agricultural pests have developed resistance to a wide range of potent chemicals”.  

This means that pesticides are no longer effective on these 300 species of agricultural pests.

Here, no longer responding to = have developed resistance to, pesticides = potent chemicals

So, the answer is: A (are no longer responding to most pesticides in use.)

Question 16: Cotton farmers in Central America began to use pesticides –

Keywords for this question: Cotton farmers, Central America, began, use pesticides,     

We find the reference of ‘Cotton farmers’ in paragraph no. 4. In lines 1-4, the author says, “. . .. . well illustrated by what happened to cotton farmers in Central America. In the early 1940s, basking in the glory of chemical-based intensive agriculture, the farmers avidly took to pesticides as a sure measure to boost crop yield.”

Here, began to use = took to, boost = to make something increase

So, the answer is: D (to ensure more cotton was harvested from each crop)

Question 17: By the mid-1960s, cotton farmers in Central America found that pesticides –

Keywords for this question: mid-1960s, cotton farmers, Central America, found, pesticides,     

In paragraph no. 5, the author says in the beginning, “By the mid-1960s, the situation took an alarming turn with the outbreak of four more new pests, necessitating pesticides spraying to such an extent that 50% of the financial outlay on cotton production was accounted for by pesticides”.

This means that pesticides accounted for 50% of the amount of money spent on cotton production.
Here, financial outlay = the money that need to be spent in order to produce cotton,

So, the answer is: D (were costing 50% of the total amount they spent on their crops)

Questions 18-21 YES, NO, NOT GIVEN

[In this type of question, candidates are asked to find out whether:

The statement in the question agrees with the claims of the writer in the passage – YES
The statement in the question contradicts the claims of the writer in the passage – NO
If there is no information on this  – NOT GIVEN

For this type of question, you can divide each statement into three independent pieces and make your way through with the answer.]

Question 18: Disease-spreading pests respond more quickly to pesticides than agricultural pests do.

Keywords for this question: disease-spreading pests, respond, more quickly, pesticides, agricultural pests,

In paragraph 2, we find a statement made by the FAO, “. . .. . more than 300 species of agricultural pests have developed resistance to a wide range of potent chemicals. Not to be left behind are the disease-spreading pests, about 100 species of which have become immune to a variety of insecticides now in use”. 

In this statement, the writer talks about the response by different pests to different pesticides. However, we find no comparison on any pests responding more quickly or less quickly than other pests.

So, the answer is: NOT GIVEN

Question 19: A number of pests are now born with an innate immunity to some pesticides.

Keywords for this question: pests, born, innate immunity, pesticides,    

In paragraph no. 3, the writer states in lines 3-5, “Because of their tremendous breeding potential and genetic diversity, many pests are known to withstand synthetic chemicals and bear offspring with a built-in resistance to pesticides”.  

The lines suggest the fact that these species are born with an innate immunity to insecticides.

Here, built-in = innate, resistance = immunity,

So, the answer is: YES

Question 20: Biological control entails using synthetic chemicals to try and change the genetic make-up of the pests’ offspring.

Keywords for this question: biological control, synthetic chemicals, change, genetic make-up, pests’ offspring,    

In paragraph no. 7, the author says in lines 1-4, “In the face of the escalating perils from indiscriminate applications of pesticides, a more effective and ecologically sound strategy of biological control, involving the selective use of natural enemies of the pest population, is fast gaining popularity – though, as yet, it is a new field with limited potential.”

Here, involving the selective use of natural enemies of the pest population means using natural enemies instead of using synthetic chemicals.

Here, synthetic means artificial.

Therefore, the question contradicts the statement given in the passage.

So, the answer is: NO

Question 21: Bio-control is free from danger under certain circumstances.

Keywords for this question: bio-control, free from, danger, circumstances,

In paragraph 7, the writer states in lines 4-7, “. . .. . .. the advantage of biological control in contrast to other methods is that it provides a relatively low-cost, perpetual control system with a minimum of detrimental side-effects. When handled by experts, bio-control is safe, non-polluting and self-dispersing”.

Here, with a minimum of detrimental side-effects = free from danger

So, the answer is: YES

Questions 22-26: (Completing sentences with correct endings)

[For this type of question, candidates need to match the beginning and ending of sentences. Candidates need to look for keywords in the sentence beginnings and find the relative paragraphs and then sentences in the passage. Skimming and scanning, both reading skills are essential for this question type.]

Question 22: Disapene scale insects feed on –

Keywords for this question: Disapene scale insects, feed on,

The last sentence in paragraph no. 9 gives us the answer to this question. The writer says here, “CIBC is also perfecting the technique for breeding parasites that prey on ‘disapene scale’ insects – notorious defoliants of fruit trees in the US and India.”

The lines suggest that disapene scale insects cause harm to fruit trees, so they feed on fruit trees.

Here, notorious = well known for being bad,

So, the answer is: D (fruit trees)

Question 23: Neodumetia sangawani ate –

Keywords for this question: Neodumetia sangawani, ate,

In paragraph no. 10, take a look at these lines, “Neodumetia sangawani, was found useful in controlling the Rhodes grass-scale insect that was devouring forage grass in many parts of the US.” 

This means that Neodumetia sangawani devoured or ate Rhodes grass-scale insect to control it from devouring forage grass. Here, ate = was devouring

So, the answer is: H (grass-scale insects)

Question 24: Leaf-mining hispides blighted –

Keywords for this question: Leaf-mining hispides, blighted,

In paragraph no. 10, the writer mentions, “In the late 1960s, when Sri Lanka’s flourishing coconut groves were plagued by leaf-mining hispides, a larval parasite imported from Singapore brought the pest under control.” 

This suggests the fact that Sri Lanka’s coconut groves were damaged by leaf-mining hispides.
Here, blight = plague, flourishing = developing quickly or being productive, grove = a small garden or group of trees,

So, the answer is: C (coconut trees)

Question 25: An Argentinian weevil may be successful in wiping out –

Keywords for this question: Argentinian weevil, may be, successful, wiping out,

In paragraph no. 9, the author mentions, “Similarly the Hyderabad-based Regional Laboratory (RRL), supported by CIBC, is now trying out an Argentina weevil (a kind of small beetle) for the eradication of water hyacinth.”

The lines suggest that an Argentinian weevil has a possibility of being successful in destroying all of the water hyacinth plants. We can guess that the weevils will eat the water hyacinth.

Here, destroying = wiping out,

So, the answer is: E (water hyacinth)

Question 26: Salvinia molesta plagues

Keywords for this question: Salvinia molesta, plagues,

Again, in paragraph 10, the writer says, “By using Neochetina bruci, a beetle native to Brazil, scientists at Kerala Agricultural University freed a 12-kilometer-long canal from the clutches of the weed Salvinia molesta. About 30,000 hectares of rice fields in Kerala are infested by this weed.”

Here, plagues = are infested by,

So, the answer is: B (rice fields)

Click here for solutions to Cambridge 8 Test 4 Reading Passage 1
Click here for solutions to Cambridge 8 Test 4 Reading Passage 3