Question 14
How many pairs of positive integers $(m,n)$ have $m/n$ in lowest terms and strictly less than 1, with $mn=1\cdot2\cdot3\cdots24\cdot25$, the product of the first 25 positive integers?
(A) $2^7$ (B) $2^8-1$ (C) $2^8$ (D) $2^9-1$ (E) $2^9$.
(A) $2^7$ (B) $2^8-1$ (C) $2^8$ (D) $2^9-1$ (E) $2^9$.