Which letter correctly labels the synapse?

According to a source, the answer is A. 

Synaptic cleft or the terminal buttons that transmits neurotransmitters to the next neuron, received by its dendrites and is relayed now throughout the system until it reaches the brain.
The messages must travel the distance of the nerves to the brain which are processed and made decisions, from the distance of the nerves from the sense organs, then travel back to the muscles that need to respond through the nerves. 

Cand d are correct because the rest are just showing your mistakes and you don’t want people who are reading a summary you wrote to see all the mistakes you made.