Which of the following is the longest part of the alimentary canal?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Small intestine
The small intestine is highly coiled and about 7.5 metres long in an adult, the longest part of the alimentary canal. Most digestion and the absorption of digested food take place here.
Why the other options are incorrect
Option (1) Oesophagus — Incorrect. The food pipe, a short tube of about 25 cm from the throat to the stomach.
Option (2) Large intestine — Incorrect. Wider but much shorter, about 1.5 metres; it absorbs water and salts.
Option (4) Tongue — Incorrect. A muscular organ in the mouth that mixes food with saliva and helps in tasting and swallowing.