The question asks us what could we infer about the generation of water bugs hatching during the summer according to the passage. Let's look at the answer choices:
(A) be made of equal numbers of macropterous and micropterous individuals
Incorrect. The passage tells us that the second-generation of water bugs that hatch during the summer have fully developed wings (macropterous) (lines 24-30).
(B) lay its eggs during the winter in order to expose them to cold.
Incorrect. The passage tells us that the second-generation of water bugs lay eggs in the spring (lines 55-58).
(C) show a marked inability to fly from one pond to another.
Incorrect. The passage tells us this overwintering generation has fully-developed wings and leave the water autumn to overwinter in forests, returning in spring (lines 27-30). Clearly, if they can fly from ponds to forests, they can also fly from one pond to another.
(D) exhibit genetically determined differences in wing form from the early spring-hatched generation.
Incorrect. The passage tells us that the differences are a result of a developmental response to environmental condition rather than genetics (lines 16-21).
(E) contain a much greater proportion of macropterous water bugs that the early spring-hatched generation.
Correct. The passage tells us that early-spring hatched generation is dimorphic - some individuals have macropterous wings, and some micropterous, whereas the second, summer-hatched generation only has individuals with fully developed (macropterous) wings (lines 25-35).
Does this make sense?
Let me know if you have any further questions.
Julie-Von September 3, 2019
Thank you for the detailed explanation! It makes sense as to why (E) is correct and the others are wrong
avifon May 26, 2020
I got thrown off by this one because the passage refers to the one's which hatch in the spring as summer ones too.
