If y/x is an integer, which of the following must also be an integer?
I. xy
II. x/y
III. x Select the correct option:
A) I alone  B) II alone  C) None of the above  D) I and III  E) III alone
Lets take X = 1/6 and Y = 2/3   Then Y/X = 4 which is an integer.   But XY = 1/6 * 2/3 = 1/9 --&gt; Not an integer.   X/Y = 1/6 divided by 2/3 = 1/4 --&gt; Not an integer.   X alone is 1/6. Not an integer.   Hence C. None of the above.
<result>C</result>
If y/x is an integer, which of the following must also be an integer?
I. xy
II. x/y
III. x