Infections by Helicobacter Pylori Cause 90% of Peptic Ulcers in the United

Infections by Helicobacter pylori cause 90% of peptic ulcers in the United States.These bacteria have pili that are only expressed in acidic conditions.A characteristic of this organism should be an ability to

A) enter the bloodstream.
B) move in the direction opposite the pili.
C) avoid ingestion by cells in the immune system.
D) attach to cells in the host organism's stomach.
E) induce a large antibody response.