How Do Three of the Five Approved Drug Treatments for Alzheimer's

How do three of the five approved drug treatments for Alzheimer's in the U.S. work to restore acetylcholine transmission?

A) They cause the neuron to release more of the neurotransmitter.
B) They prevent the neurotransmitter from being recycled back into the neuron.
C) They cause the receptors to become more sensitive to the neurotransmitter.
D) They interfere with the enzyme that breaks down the neurotransmitter at the synapse.