问一道题目

miguel29

(a/b)/c
In the expession above, a,b, and c are different numbers and each is one of the numbers and each is one of the numbers 2,3,or 5. What is the least possible value of the expression?
A,1/30
b,2/15
c,1/6
d,3/10
e,5/6
这题的意思是问下列个那个数最不可能吗？为什么啊？当是a=2,b=3,c=5的时候不就是B吗？