Women’s volleyball is a ‘head count’ sport in D1, so if there is a scholarship offered from a D1 school (and that sport is fully funded) it will be a full COA scholarship (or none at all). For D2, she can stack a volleyball scholarship with an academic one but not with a needs based scholarship from the school. She can combine athletic with merit or need based aid from federal or state sources.
That said, a scholarship from a D1 is very very difficult to get.
there are no athletic scholarships in D3, so she’s free to accept merit or need based scholarships.