The correct option is C 23
Givem fraction is mn where m is an integer.
For mn to be a terminating decimal number, n should be a power of 2, 5 or multiplication of power of 2 and 5.
When n=32:
32=4×8=(2×2)×(2×2×2)
Hence, 32 is a possible value of n.
When n=30:
30=3×10→3 in the denominator may not get canceled out and result in a non-terminating decimal number.
When n=23:
mn=m23=3×m2
The denominator is a power of 2, hence, this value of n will result in a terminating decimal number.