Jakob is asking to simplify the expression -3a + 4b + 5a + (-7b).
He writes: -3a + 4b + 5a + (7b) = -3a + 5a + 4b + (7b).
Which property allows him to do this?
A. the associative property
B. the commutative property
C. the distributive property
D. the additive identity property