Activity of the Neurotransmitter Acetylcholine Is Brief Because It

Activity of the neurotransmitter acetylcholine is brief because it

A) is pumped out of the synaptic cleft by the sodium- potassium pump.
B) is transported back into the presynaptic neuron.
C) diffuses out of the synaptic cleft.
D) is rapidly broken down by enzymes in the synaptic cleft.
E) "self- destructs" shortly after leaving the presynaptic neuron.