Forty students watched films, A, B and C over a week. Each student watched either only one film or all three. Thirteen students watched film A, sixteen students watched film B and nineteen students watched film C. How many students watched all three films?
Correct Option : C
13 + 16 + 19 = 48 > 40 Hence, 4 students would have watched all three due to which there is a double counting of 4 × 2 = 8.