The easiest way to compare fractions is when they have the same common denominator. Then it is simple a matter of comparing the respective numerators...
5/8 and 2/4 is equivalent to
5/8 and 4/8 so they are not equal...
2/4 and 4/8 is equivalent to
4/8 and 4/8 so they are equal.
3/8 and 2/4 is equivalent to
3/8 and 4/8 so they are not equal
2/4 and 2/8 is equivalent to
4/8 and 2/8 so they are not equal
Thus the only pair that are equal is:
2/4 and 4/8 B)