What is the algebraic expression for the following word phrase: the difference between 17m and 3?

A. 17m + 3
B. 17m x 3
C. 17m / 3
D. 17m - 3
YA'LL HELP ME I DONT NEED THE ANSWER JUST EXPLAIN IT TO ME PLEASE

To find the difference between two numbers, subtract second number from the first number.

17 m - 3