The question refers to vegetation types or ecosystems, and to the extent they have been studied.
(A) There is no question of vegetation types or ecosystems hindering or preventing ecologists from
studying them. Perfecting the study of vegetation types and ecosystems does not
(B) The underlying contrast in the sentence is clearly brought out by the idea that there are no ecosystems whose study has been exhausted or completed freely that they are no longer of
any interest to ecologists.
(C) If the study of ecosystems has been prolonged then the study would likely continue. Therefore it is incorrect to say that further study of ecosystems do not require ecologists.
(D) If the study of ecosystems has been prevented by some means or the other they do present a challenge to ecologists.
(E) It is illogical to say that the study of vegetation types or
ecosystems benefits ecologists. It is difficult to imagine how delaying
the study of vegetation types or ecosystems will no longer benefit
The correct answer is option B.
Percent correctly answered: 81.