Which of the following is an example of a short chain fatty acid?

• A. Lauric acid
• B. Stearic acid
• C. Oleic acid
• D. Butyric acid

Answer: (D)

Short-chain fatty acids are defined by a small carbon backbone, typically up to six carbons in length. Butyric acid has four carbons (a butanoic acid), placing it squarely in this short-chain category. In contrast, lauric, stearic, and oleic acids have much longer chains—twelve or eighteen carbons—so they are long-chain fatty acids (with oleic also being unsaturated). Because the question is about a short-chain fatty acid, butyric acid is the correct example.