The correct option is
A Eutherian
(A) Eutherian are mammalian clade consisting of Cretaceous. For example-Scaly anteater.
(B) Metatherian are the mammalian clade consisting of classes close to marsupials.
(C) Prototherians are the mammalian clade consisting of egg-laying monotremes.
So, the answer is 'Eutherians'.