The swallowed food moves downwards in the alimentary canal because of (a) force provided by the muscular tongue. (b) the flow of water taken with the food. (c) gravitational pull. (d) the contraction of muscles in the wall of the food pipe.

Soln:

The answer is (d) the contraction of muscles in the wall of the food pipe.

Explanation:

Muscles of the Esophagus push food down by the movement of the wall of the food pipe. Actually, this movement takes place throughout the alimentary canal and pushes the food downwards.