एक मानव वयस्क का पूरा पाचन तंत्र मुंह से गुदा तक लगभग _______ मीटर लंबा होता है। A. 8 B. 7 C. 10 D. 9

The adult human digestive tract, from mouth through oesophagus, stomach, small and large intestine to the anus, is about 9 metres (roughly 30 feet) long. The small intestine alone accounts for about 6–7 m of it.