Question

Which one is not an animal?

Answer 1

B: El maiz it is corn

Answer 2

B) El maíz.
=
Corn.

Why? 
A) El ganso is a goose; we all know a goose is a bird and a bird is a/n animal.

C) La gallina is a chicken, which is also a bird, and as I said previously, a bird is a/n animal.

D) El lobo is a wolf, which is a mammal; which is an animal.

This is how we get B) El maíz.

Hope this helps!~