The correct answer is D) Compartments for the storage of canned drinking water. Motor-propelled lifeboats are required to be equipped with compartments to store canned drinking water, as per the regulations for lifesaving equipment on commercial vessels. This ensures that survivors have access to potable water in an emergency situation at sea. The other answer choices are incorrect because: A) An air starter is not a mandatory requirement for motor-propelled lifeboats, B) Auxiliary mechanical propulsion is not a standard feature, and C) Ballast tanks are not specifically required, as the boat's design should prevent capsizing.