Studies Examining the Extent to Which a Child's Response Style

Studies examining the extent to which a child's response style is evident early in the child's life have found that

A) temperament does indeed begin in the womb.
B) temperamental differences between newborns are still evident years later.
C) irritability and negative responses are the only persistent temperamental differences between individual children.
D) infant development is so variable evidence can only be inconclusive.