Hey there!
The answer is B, the commutative property of multiplication.
The commutative property of multiplication states that you get the same value in an expression, not depending on the order. See here, you have -3/9 and 2, and even though they're in different orders, when you multiply them, they're equal.
Notice how it doesn't work in other operations such as subtraction and division (it works in addition):
10/5 ≠ 5/10
4-10 ≠ 10-4
However,
5 + 10 = 10 + 5
Hope this helps!