If gastric juice has a pH of about 1.5,which of the following would be predominantly deprotonated in the stomach?

A)phenol (pK_a = 9.9)
B)acetic acid (pK_a = 4.7)
C)lactic acid, (pK_a = 3.9)
D)phosphoric acid (pK_a = 2.1)
E)hydrochloric acid (pK_a = -6)