Which of the Following Is Not True

Which of the following is not true:

A) post hoc analyses of main effects are minimized or sometimes not conducted at all if the interaction is significant
B) a post hoc analysis is not required of a significant main effect whose df = 1
C) a post hoc analysis is not required of a significant main effect whose df = 2
D) a post hoc analysis is not required of a nonsignificant interaction