AI-generated practice question — model-generated for extra practice, not a previous-year CBSE board question.
Option C — Small intestine.
The complete digestion of carbohydrates, proteins and fats takes place in the small intestine.
The small intestine receives secretions from the liver (bile) and pancreas (pancreatic enzymes) that complete the digestion of all three food types. Partial digestion begins earlier (mouth for carbohydrates, stomach for proteins), but completion happens only in the small intestine — this distinction is key for MCQs.