In a nationwide poll,N people were interviewed.If 1/4 of them answered "yes" to question 1,and of those,1/3 answered "yes" to question 2.Which of the following expression represents the number of people interviewed who did not answered "yes" to both questions. (A) N/7 (B) 6N/7 (C) 5N/12 (D) 7N/12 (E) 11N/12