Caffeine can kill or inhibit the growth of the larvae of several species of insects. One recent experiment showed that tobacco hornworm larvae die when they ingest a preparation that consists in part of finely powdered tea leaves which contain caffeine. This result is evidence for the hypothesis that
the presence of non-negligible quantities of caffeine in various parts of many diverse species of plants is not accidental but evolved as a defense for those plants.The argument assumes that
Highlighted text is the conclusion of the argument. Two things that matter here are:
1. That preparation consisting of powdered tea leaves that contain caffeine as it is non-negligible.
2. Non-negligible quantities of caffeine in various parts of many diverse species of plants being an EVOLVED defense for those plants.
(A) caffeine-producing plants are an important
raw material in the manufacture of commercial insecticides - WRONG. Irrelevant.
(B) caffeine is stored in leaves and other parts of caffeine-producing plants
in concentrations roughly equal to the caffeine concentration of the preparation fed to the tobacco hornworm larvae - WRONG. Big trap and its worth it. May be true but it is not related to evolution part that conclusion makes.
(C) caffeine-producing plants
grow wherever insect larvae pose a major threat to indigenous plants or once posed a major threat to the ancestors of those plants - WRONG. Worst possible choice.
(D) the tobacco plant is among the plant species that produce caffeine for their own defense - WRONG. This is a nice inference but not an assumption. Also, conclusion is not ONLY about tobacco plants.
(E) caffeine-producing plants or their ancestors have at some time been subject to being fed upon by creatures sensitive to caffeine - CORRECT. The word 'evolved' is the keyword here. Only if their ancestors were subjected to being fed up, evolution happened.
Answer E.
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Pain + Reflection = Progress | Ray Dalio
Good Books to read prior to MBA