The Following Is a Series of Events That Occur at a Typical

The following is a series of events that occur at a typical cholinergic synapse. Place the events in the correct sequence. 1. Calcium ions enter the cytoplasm of the synaptic knob and ACh release occurs.
2) Arriving action potential depolarizes the synaptic knob and the presynaptic membrane.
3) Depolarization ends as ACh is broken down into acetate and choline by AChE.
4) ACh release ceases because calcium ions are removed from the cytoplasm of the synaptic knob.
5) The synaptic knob reabsorbs choline from the synaptic cleft and uses it to resynthesize ACh.
6) ACh diffuses across the synaptic cleft and binds to receptors on the postsynaptic membrane.
7) Sodium channels on postsynaptic surface are activated, producing a graded depolarization.
The correct sequence of events is

A) 2, 1, 6, 7, 4, 3, 5.
B) 2, 6, 4, 1, 3, 5, 7.
C) 1, 3, 5, 7, 2, 4, 6.
D) 1, 2, 4, 5, 3, 6, 7.
E) 7, 4, 5, 6, 2, 3, 1.