PT02.S02.Q18 - Learning how to build a nest..

HoneyCabbage-1-1

I am having a hard time understanding the rationale behind the correct answer choice being 'B' and why it wouldn't be choice 'D'

kanel1995

This is how I understand it: naturally to weaken this argument would be to find something other than blackbird's "nesting experience" to account for this observation. B does that: if their eggs naturally get more viable the older they get, that would explain their increased reproductive success. It's not that older birds are more capable of looking after their young (experience), for example, it's just that their eggs get better with age.

Conversely, I don't think D weakens the argument. What D is saying does not serve as an alternative explanation for what Dr. Snow observed. Some might even say it borderline strengthens the argument, since the author already said "This cannot be a mere matter of size and strength...".

I hope this helps.