Monotremes are mammals that reproduce by laying eggs, and well, platypuses are mammals, and they lay eggs. Given these facts, a platypus is an example of _. among the following options:
- Marsupial.
 - Monotremes.
 - insects
 - animals
 - killing insects
 - Amphibian.
 - Placental mammal.
 - matter vibrating


 

  Monotremes.       