The Model Below Predicts That the Begging Level of Full

The model below predicts that the begging level of full (satiated) offspring (F) should essentially be zero, whereas hungry (H) and starving (S) offspring show intermediate and high levels of begging, respectively. Under what circumstances would we expect full (satiated) offspring to start begging?

A) when the fitness costs of begging are higher than the benefits
B) when the fitness costs of begging are lower than the benefits
C) only when the fitness costs of begging increase in a nonlinear fashion with begging intensity
D) Under no circumstances would this occur; the full (F) individuals are by definition at begging intensity zero.