why is the third answer not A ?

This a tricky one very difficult to grasp. I have some reflection on it as well

A simply is not stated in the passage

B is the consequence of this balance

As such, it is likely that organismal color reflects a balance among numerous and perhaps competing demands; a color best suited for the performance of one function (e.g., avoidance of predators) may reflect a trade-off with that suited for another (e.g., attractiveness to potential mates).

Basically, it depends on the context and the environment, the color has been developed for one thing, and instead, it would be best useful for another to the animal. Therefore, after all that color does not serve that much to the specific purpose and this could put in peril the animal itself.

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Could you explain the last question in more detail, pls?

How option C is also correct for Q2? There's nothing mentioned about ancestors or previous gen. in the passage.

OE

1) (C) If the researchers are calling the explanation a “useful way to tie” things together, it makes sense that “hailed” means lauded (praised) in this context

2) (B, C) Like any trait that current organisms possess, conspicuous markings must exist because organisms with them are the offspring of previous generations that survived long enough to
reproduce. By saying that there is a “trade off” in terms of color function, the author implies that any trait would not exist unless it had a corresponding benefit to the organism’s survival, and
therefore, its reproduction. He also implies that conspicuous markings may be detrimental to an organism, contrasting them with cryptic (camouflaging) markings, giving further evidence that being conspicuous must help an organism breed, (B). Choice (C) is also supported by this reasoning

3) (B) By saying that an organism’s color is an “adaptive function,” the author implies that its color can help the organism in different ways at different times, which supports the assertion that these demands may be “competing,” i.e., a color that helps with one demand may be unhelpful for another.
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