What vessels show two red lights as well as anchor lights?

In accordance with the Regulations, vessels at anchor are required to exhibit specific lights to clearly communicate their status to other vessels. When a vessel is at anchor, it shows an all-round white light at its stern and an all-round white light at the bow, but it also has the option to show two red lights vertically, which indicate to other vessels that it is at anchor. This is especially important during times of reduced visibility or darkness, as it helps to prevent collisions by signaling to other boaters that the vessel is not moving.

The choice regarding vessels aground only requires that they display three lights or shapes (one at the bow and one at each side, in addition to an all-round white light) but does not specify the use of two red lights in conjunction with anchor lights. Vessels engaged in fishing and all vessels underway do not typically display two red lights as part of their navigation lighting requirements; instead, their lighting configurations are designed to indicate their respective activities and statuses on the water. Thus, the specific requirement for two red lights is exclusively applicable to vessels at anchor, affirming why this choice is the correct response.