The correct choice is (c) 11
The explanation is: The question requires you to find number of the outcomes in which at most 2 coins turn up as heads i.e., 0 coins turn heads or 1 coin turns head or 2 coins turn heads. The number of outcomes in which 0 coins turn heads is ^4C0 = 1 outcome. The number of outcomes in which 1 coin turns head is ^4C1 = 6 outcomes. The number of outcomes in which 2 coins turn heads is,
^4C2 = 15 outcomes. Therefore, total number of outcomes = 1 + 4 + 6 = 11 outcomes.