Answer : 3. "Synaptic cleft"
Explanation :

Answer: C) Synaptic cleft Explanation: A neuron or nerve cell is a cell that carries electrical impulses. Neurons are the basic units of the nervous system and its most important part is the brain. Every neuron is made of a cell body (also called a soma), dendrites and an axon. Dendrites and axons are nerve fibres.   The gap between two communicating neurons is termed Synaptic cleft.