Most Helpful Girl
They can be necessary for most sizes.
Women with small boobs may want them too look larger. Women with big boobs may want them to look more firm and raised. No matter what size, wearing a regular T-shirt bra will not give the same affect as a push up unless the bra is 10 times too small.
Most Helpful Guy
C and above in my opinion. To me, push up should never be used.
For someone I like, I wouldn't care still if she had A or B cup size