Which of the Following Is NOT True

Which of the following is NOT true?

A) When the dorsal respiratory group stops firing, expiration occurs.
B) The ventral respiratory group becomes active during periods of increased ventilation.
C) In mammals it is thought ventilation rhythm is established in the pre-Botzinger complex.
D) The pneumotaxic center sends impulses to the dorsal respiratory group that help switch on the inspiratory neurons.
E) None of these.