The correct choice is (c) 26
Easiest explanation - Consider sample space S={1,…100}. Consider three subsets A, B, C that have elements that are divisible by 2, 3, 5 respectively. Find integers that are divisible by A and B, B and C, A and C. Then find the integers that are divisible by A, B, C. Applying the inclusion-exclusion principle, 100 − (50 + 33 + 20) + (16 + 10 + 6) − 3 = 26.