Traveling to US on B2 while GC is being processed

[blah]

If a girl has B2 tourist visa, and later she gets married to a GC holder in US, and she applies for GC under F2A category, will she be able to visit US while GC is being processed ?

Can customs officer at US turn her back due to immigration intent, even though she already had B2 before applying for GC ?

[jnk]

Yes.
Possibly.