Answer;
Vesicles containing neurotransmitter.
Explanation;
-Neurotransmitters are released by secretion from the ends of axonal terminals.
-Synaptic vesicles store various neurotransmitters that are released at the synapse.
-Neurotransmitters are released from the axon terminal when their vesicles "fuse" with the membrane of the axon terminal, spilling the neurotransmitter into the synaptic cleft.
C as far as I know. Hope this helps!
The answer should be both