Gluten is best described as a carbohydrate found in wheat and related grains a medication used to treat celiac disease a protein found in wheat and related grains a substance found in wheat and related grains that causes irritable bowel disease q

Gluten is actually a "protein found in wheat and related grains". Gluten is clinically significant for being associated to Celiac disease or tropical sprue. Gluten is not a carbohydrate; is not a medication to treat Celiac disease (but rather causes it); and gluten does not directly cause irritable bowel syndrome.

I think that according to the options listed the best answer would be Gluten is best described as a protein in wheat and related grains. A disease called celiac is suffered by people who are allergic to gluten. Some people tend to think that irritable bowel disease is caused by gluten but this is false. The cause of irritable bowel disease is not well known. 
 

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