Question

The stone canal of starfish is

• A. Reproductive canal
• B. Respiratory canal
• C. Excretory canal
• D. None of the above

Answer 1

The correct option is D None of the above

Starfish is an echinoderm which has water vascular system. They have a central canal and tube-like channels in the tube feet. The water enters by madreporite which is further circulated by stone canal to the ring canal and into the radial canals. The radial canals carry water to the ampullae and provide suction to the tube feet. So, the stone canal is a part of water vascular system.
Therefore, the correct answer is option D.