Please check my answers before I turn in this test

1.Which word in the sentence is the predicate nominative?

A killer whale is a mammal with a black body and white patches.

A.patches
B.body
C.mammal D.whale

2.Which word in the sentence is the predicate nominative?

Down the road, that dark shape might be a dog.
A.dog B.road
C.shape
D.dark

3.Which word in the sentence is the predicate nominative?

They are two of the best skaters in our town.
A.skaters
B.town
C.They
D.two