prep这道题要用到概率的知识吗？

carolcai

143.  14954-!-item-!-187;#058&010212

In a survey of students, each student selected from a list of 12 songs the 2 songs that the student liked best.  If each song was selected 4 times, how many students were surveyed?

 

(A) 96

(B) 48

(C) 32

(D) 24

(E) 18

shiverson

用不着吧我觉得...所选出来的里面，12首歌各4票，一共48票，每票投两首，24人吧...