Which of the following is NOT one of the assumptions of Lack's hypothesis?

A) There is no trade-off between a parent's reproductive effort in one year and its survival or reproductive performance in future years.
B) The only effect on clutch size of offspring is in determining whether the offspring survive.
C) The discrepancy between Lack's hypothesis and the behavior of individual birds may sometimes be more apparent than real.
D) All of these are assumptions of Lack's hypothesis.