Provide your best answer for the following math problem. Give ONLY the answer, no other words or explanation.
For example:

Answer: <most likely answer, as short as possible; not a complete sentence, just the answer!>.

The problem is: if m and n are positive integers and n ≠ 1 , then mn ( n − 1 ) is
mn ^ 2 - mn
m(n-1)n.