Answer:
The leading cause of peptic ulcer disease is currently believed to be infection of the stomach by a bacteria is called Helicobacter pylori.
Step-by-step explanation:
An infection that develops from Helicobacter pylori bacteria is one of the most common causes of peptic ulcers. It’s not clear how an H. pylori infection spreads, but it is believed that it may be transmitted from person to person through close contact.
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