I'll give you a question, please answer with step-by-step reasoning process.
A fair coin is tossed repeatedly. If head appears on the first four tosses, then the probability of appearance of tail on the fifth toss is.\nOptions:\n(A) 1/7\n(B) 1/2\n(C) 3/7\n(D) 2/3\n(E) 1/3

(B)
Since the coin is a fair coin, every toss is independent of any other toss.

Hence, the probability of appearance of tail on the fifth toss is = 1/2.

The answer is (B)