Which triple therapy is commonly used for treating peptic ulcer disease (PUD) secondary to Helicobacter pylori infection?
a) Amoxicillin, clarithromycin, and metronidazole
b) Omeprazole, sucralfate, and rifampin
c) Cimetidine, azithromycin, and tinidazole
d) Lansoprazole, doxycycline, and levofloxacin