Number of synapses

In a reflex arc that comprises a pain receptor cell in the skin, three neurons and a muscle (effector). The number of synapses found in the central nervous system (CNS) is:

A. 3
B. 5
C. 4
D. 1
E. 2

there are 2 synapses in the CNS, a synapse between sensory and relay neuron in the CNS and the other between relay neuron and motor neuron, As there are three neurons playing a role in this reflex arc.