I'll give you a question, please answer with step-by-step reasoning process.
A platypus is an example of _.\nOptions:\n- (A) Marsupial.\n- (B) Monotremes.\n- (C) insects\n- (D) animals\n- (E) killing insects\n- (F) Amphibian.\n- (G) Placental mammal.\n- (H) matter vibrating

(B)
Monotremes are mammals that reproduce by laying eggs.

Well, platypuses are mammals, and they lay eggs.

Platypuses are monotremes.

.

The final answer: (B)