Four words have been given, out of which three are alike in some manner and one is different. Select the odd one.

Peacock, Woodpecker, Parrot, Bat

Peacock, Woodpecker, and Parrot are all birds that can fly.
Bat, however, is a mammal and not a bird, even though it can fly.
 Bat, as it is different from the rest in classification.

Thus, the correct answer is B.​​