Sentence:This year's Nobel Laureates in Physiology or Medicine made the remarkable and unexpected discovery that inflammation in the stomach (gastritis) as well as ulceration of the stomach or duodenum (peptic ulcer disease) is the result of an [e1]infection[/e1] of the stomach caused by the [e2]bacterium[/e2] Helicobacter pylori.
 e1: infection. 
 e2 : bacterium.
Answer: Cause-Effect(e2,e1)