Will 295cc under help me achieve a D cup? (Photo)

Iv been really struggling with deciding between over or unders as my consultant has said I can choose I am quite an empty b cup after having my son I'm flat on the top pole and would like more fullness at the top, however I know there is more benefit to having unders but my concern is will I loose the fullness at the top? Would it be better for me to go from moderate plus to high profile to achieve a better top clevage and will 295cc get me from a b cup to a nice d cup? thanks