Question

Mi mamá __________ los calcetines azules por los calcetines blancos.

cambio

cambia

cambian

cambiamos

Answer 1

You would use cambia(:

Answer 2

NO you would use Cambio. Cambia is present tense.
With Cambio: Mi mama cambio means my mom changed or switched....
With Cambia: Mi mama cambia, means my mom CHANGES....

My mom changed or switched the blue socks for the white socks
Mi mama CAMBIO los calcetines azules por los calcetines blancos.

Answer 3

"Cambio" actually means "I change."

"Cambió" means "(He/She) changed."

The accent really matters.

Answer 4

@InYourHead is right. So if there isn't an accent mark on cambio, then cambia would make more sense.

Answer 5

Spanish courses tend to confuse. I'd suggest you ask your teacher what they are actually asking for in this type of questions.

Hispanic + taking Spanish II (for the credits)