In a neuromuscular synapse, which of the following breaks down the neurotransmitter released from the axon?
a. the enzyme acetylcholinesterase
b. the motor end plate
c. the arrival of additional impulses at the axon terminal
d. the creation of additional synaptic vesicles

Acetylcholine is the neurotransmitter released by cholinergic neurons responsible for contracting muscles (one of the major) and by learning and memory. In the case of muscle contraction, nerve transmission (in this case called neuromuscular transmission) occurs at a site called the neuromuscular junction, where the axon splits into several endings and binds to skeletal muscle fiber.   It is the product of the reaction between choline (lecithin component) and acetyl-CoA in the presence of the enzyme choline acetyltransferase.

A.The enzyme acetylcholinesterase