The correct answer is A) righting lines. Righting lines are specifically designed to help turn over a capsized liferaft and return it to its upright position. They are attached to the underside of the liferaft canopy and can be pulled to flip the raft over. This is a key safety feature to ensure the liferaft can be accessed and used in the event of a capsize. The other options are incorrect because they serve different purposes - manropes are for holding onto when entering the raft, the sea painter is for securing the raft to the vessel, and the canopy is the main cover of the raft, not a mechanism for righting it.