What Is the Evidence That a Newborn Infant Can Detect

What is the evidence that a newborn infant can detect the difference between "ba" and "pa" sounds?

A) An infant can learn to look one direction after hearing "ba" and a different direction after hearing "pa."
B) An infant smiles after hearing a "pa" sound but not after hearing a "ba" sound.
C) An infant learns to suck harder to turn on a "pa" sound, but not to turn on a "ba" sound.
D) After habituating to a "ba" sound, an infant sucks harder after hearing "pa."