In This Close-Up Image of a Lung,what Structures Are Indicated

This figure shows respiratory control centers in the brainstem.What does number 2 indicate? A)Central chemoreceptors B)Pontine respiratory group C)Dorsal respiratory group D)Ventral respiratory group

This figure shows respiratory control centers in the brainstem.What does number 3 indicate? A)Pontine respiratory center B)Central chemoreceptors C)Dorsal respiratory group D)Ventral respiratory group