A Characteristic Limitation of Mischel's Viewpoint Is

A characteristic limitation of Mischel's viewpoint is:

A) The explanation of his most important cognitive variables need more details
B) His emphasis on life task research at the expense of personalistic research
C) Some of his most important concepts, such as delay of gratification, have not been verified by the research of others
D) b & c
E) a, b, & c