Some Scientists Believe That All Mammal Species Have Already Been

Multiple Choice

Some scientists believe that all mammal species have already been discovered and named. Recently, however, a biologist in Southeast Asia published a photograph of what appears to be a new species of cat. Claiming that the cat is in fact a new species is premature though, because _____________________.
Which one of the following, if true, most logically completes the sentence?

A) Biologists cannot determine the existence of a new species without examining the animal itself, not just a photograph.
B) It was not previously known that large cats still lived in that area of Southeast Asia.
C) Other biologists still assert that all mammal species have already been discovered.
D) Prior research initiatives in Southeast Asia did not document the existence of this new species.
E) Several biologists observed the photograph and stated that they believe it is in fact a new species.