From the Studies That Applied Piaget's Theory to Animals, We

From the studies that applied Piaget's theory to animals, we can conclude that many concepts described by Piaget

A) were not meant to apply to the thought processes of any animals.
B) are involved in solving real-world problems facing most animals.
C) are applicable to the cognition of humans only.
D) are involved in the cognitive processes on humans and primates only.