A person gets Rs. 100 if a head turns up and loses Rs. 50 if a tail turns up when an unbiased coin is tossed. If three unbiased coins are tossed simultaneously then the probability that the person neither gains nor loses is

A

$$\frac{1}{2}$$

B

$$\frac{3}{8}$$

C

$$\frac{5}{8}$$

D

$$\frac{1}{5}$$