Should my out-of-state college student daughter file a state tax return in the state where she is attending college, California, in order to get a refund of state taxes?

I'm doing taxes for my daughter, who is going to school out of state and earned money in that state. 

I am in Oklahoma and my daughter lists our home as her permanent address. She is going to school in California. She earned money in CA and had CA state income tax deducted from her wages. She has no income from Oklahoma.

Should she file a CA tax return to get her refund from CA?

Should she also file an Oklahoma tax return, because that’s her permanent residence, even though she has no Oklahoma income?