Answer:
D
Explanation:
B is not correct.
Convention says that the number after the divide sign must be in the denominator. In plain English, that means you must have 18 on the top and 15 on the bottom like this
18
===
15
Since that is not one of your answers you have to break it down
18 can be divided by 15 once. That means that A is not right either.
So all you have left is C and D
There's 3 left over when you divide 18 by 15.
Only one answer is possible
1 3/15 which is D