The contraction of the _________ causes active inhalation, and is normally ... ...

The contraction of the _________ causes active inhalation, and is normally involuntarily controlled by respiratory centers located in the _________.
(A) Diaphragm; brainstem
(B) ...
(C) ...
(D) ...
(E) ...

*This question is included in 16. The Digestive, Respiratory, and Urinary Systems: Absorption and Excretion