Answer:
Platypus
Explanation:
Monotremes is one of the group off mammals among the three mammalian groups. Monotremes have structural differences in the their digestive tract, jaws and brain. Monotremes member are viviparous.
Platypus is a monotreme because it lays eggs and shows differences in the jaws and brain structure with other mammals. The platypus shows similar characteristics with the other members of monotremes.
Thus, the correct answer is option (B).
