The correct answer is D) lifelines on the inside of the raft. Lifelines on the inside of an inflatable raft help keep people stationary in rough weather by providing something for the passengers to hold onto. This prevents them from being tossed around inside the raft, which could lead to injuries. The lifelines give the passengers a secure handhold to maintain their position and stability, even in choppy seas or high winds. The other answer choices, such as straps from the overhead, lashings on the floor, or ridges in the floor, do not directly address the issue of keeping people stationary in the raft. While these features may provide some stability, lifelines are the primary design element that helps prevent passengers from being thrown around inside the raft during rough conditions.