Most common cause of traveller’s diarrhea is –
**Core Concept**
The most common cause of traveller's diarrhea is related to the consumption of contaminated food or water, leading to a gastrointestinal infection. This condition is often caused by **bacterial pathogens**.
**Why the Correct Answer is Right**
The correct answer is related to the most prevalent bacterial cause of traveller's diarrhea, which is **Enterotoxigenic Escherichia coli (ETEC)**. ETEC produces **enterotoxins** that stimulate the intestinal lining, causing excessive fluid secretion and leading to diarrhea.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because while other bacteria can cause diarrhea, they are not the most common cause.
**Option B:** Incorrect as it is not the primary bacterial cause of traveller's diarrhea.
**Option D:** Incorrect because viral causes, although possible, are less common than the bacterial cause in question.
**Clinical Pearl / High-Yield Fact**
Traveller's diarrhea can be prevented by avoiding contaminated food and water, and **ETEC** is a key target for prevention and treatment strategies.
**Correct Answer:** D. Enterotoxigenic Escherichia coli (ETEC)