Task: Question Answering
Input (English): Problem: the probability is 1 / 2 that a certain coin turns up heads on any given toss. if the coin is tossed 6 times, what is the probability that the coin turns up tails on at least one of the tosses ?
Options: a. 15 / 16, b. 21 / 32, c. 31 / 32, d. 63 / 64, e. 51 / 64
Output (English): d