A coin is tossed successively three times. Find the Probability $(P)$, Event $(E)$, Sample space $(S)$ of getting exactly one head or two heads, where $n$ is number of occurrence.

(A) $n(S)=8$ and $n(E)=4$

(B) $n(E)=6$ and $n(S)=8$

(C) $P(E)=\frac{3}{4}$

(D) $P(E)=\frac{1}{2}$

Choose the correct answer from the options given below :