Pest Control

Answer and linking clues

Correct order: C, A, D, B

1. C. Chemical pest control dates back 4,500 years, when the Sumerians used sulfur compounds as insecticides.
2. A. The Rig Veda, which is about 4,000 years old, also mentions the use of poisonous plants for pest control.
3. D. And the ancient Chinese and Egyptians are also known to have used chemical pest control.
4. B. But it was only with the industrialization and mechanization of agriculture in the 18th and 19th centuries, and the introduction of the insecticides pyrethrum and derris that chemical pest control became the method of choice.

Why this order

• C comes first: it introduces the topic and needs no sentence before it.
• A follows C: it opens with “The Rig”, which points back to something already mentioned; it picks up “years”, “pest” from C.
• D follows A: it picks up “pest”, “control” from A.
• B follows D: it picks up “chemical”, “pest” from D.

RealPTE numbers

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From RealPTE practice records and students’ “I sat this” reports, counted weekly (last count 2026-10-21). Reports are what students tell us; predictions are not guaranteed.

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