When entering from seaward, a buoy displaying a composite group (2+1) flashing red light indicates __________.

Correct Answer: Option D — a junction with the preferred channel to the left

A composite group flashing (2+1) light is reserved for preferred channel buoys. When entering from seaward, a (2+1) red light indicates the preferred channel is to the left (port), meaning the buoy should be left to starboard to remain in the primary channel.