My wife has a b2 visa and im applying for her k3

[ARL10]

My wife has a b2 vis that expires in Dec this year, if i start the application for her K3 visa to come here to the US will she still be able to come visit on her B2 visa or will that b2 visa automatically be invalid?

[ARL10]

Is it possible for her to have to types of visas at the same time? she is still planning to visit here in the US while her B2 visa is still valid..