Why social distance is regarded as one of the key measures to prevent the spread of Corona virus

Corona  can spread through coughing, sneezing and close contact. By minimizing the amount of close contact we have with others, we reduce our chances of catching the virus and spreading it.

we have to select the terms that are associated with communication between neurons.

synapse is the gap between two neurons that is there to transmit the signal.

from one neuron to other neuron the signals transmit through neurotransmitter which is a chemical and finally after reaching it becomes the electrical signal

therefore, option 4th is correct that is: synapse,electrical signals and neurotransmitter.