Henry Dale's Assertion That Neurons Could Contain Only One Type

Henry Dale's assertion that neurons could contain only one type of chemical messenger is​ 

A) correct. 
B) incorrect, as some neurons can release two small molecules in different locations. 
C) partially correct, in that neuropeptides are never found in the same neuron as amines or amino acids. 
D) partially correct, as neurons nearly always release more than a dozen neurotransmitters whenever stimulated.