i received a private message about this stuff.

vikram4689 wrote:ok, so do you mean that since scientist are comparing UN-fused clavi. of thero. with fused ones of birds, scientists wanted to convey that theropods did not be have FUSED clavi because in that case scientist would have compared FUSED ones of thero and birds.

you have somewhat of a point here, in the sense that RC inferences usually leave no gaps between ideas. but, these doubts should all fly away into the night sky as soon as you look at the other four choices, all of which are obviously wrong. (A and C are the opposite of the arguments made; E is an argument FOR the evolution of birds from theropods; B is not an argument for either side.)

you should very quickly realize that your objection to choice (d) is basically nitpicking, whereas the other four choices are 100% clearly and plainly wrong. if you don't see the difference, then you have to develop that ability, or else you are going to be in a world of trouble on this exam.

i am convinced that a,b,c,e are wrong but even after doing POE and spending around 3min., i marked "b"

you were convinced that four choices were incorrect, but then you picked one of those four choices?
hmm
again, this boils down to the problem mentioned above.
your real task here is to pick the answer that's better than the other answers. if no answer is perfect, then that often boils down to the task of differentiating between finding serious issues and finding petty, hair-splitting objections (which, needless to say, is something that's going to be pretty important if you are actually thinking of a career in business management).

vikram4689 wrote:actually i thought that test-makers are trying to confuse me by mentioning un-fused clavicles of theropods as only clavicles mentioned in passage are fused ones. so i tried to out-smart them by not choosing d)

yeah fine, but hopefully it's clear now that you shouldn't do that unless there's actually another answer choice that could conceivably be correct.

in this problem it should be quite clear that the other four answer choices are totally wrong, so it should be apparent that this is not a "trap answer" kind of situation.