Problem Solving

The numbers \(m, n,\) and \(K\) are all positive integers. Given that \(m\) is a factor of \(K,\) that \(n\) is also a factor of \(K,\) and \(m < n,\) which of the following must also be a positive integer factor of \(K?\)

A. \(m + n\)

B. \(mn\)

C. \(\dfrac{n^2}{m}\)

D. \(\dfrac{K}{m}\)

E. \(\dfrac{K}{mn}\)

Answer: D

Source: Magoosh