But wait, I have read in multiple places that large breast will do what happens in B if someone is wearing clothing. In fact I have a Greek friend who has natural large breasts(her whole family has large breasts) and they do exactly what happens in B when she wears a top with a plunging neckline.
It'd vary from person to person I say! Boobs are almost like fingerprints in a sense, no two pairs are the same! It can also depend on what kind of bra you're wearing too, I'm pretty chesty myself and I can only get cleavage/have boobs like the B example if I wear a normal bra and a sports bra (or just a small-ish sports bra).