Which signal indicates entering the lock with caution?

Which signal indicates entering the lock with caution?

• A. Flashing Amber and Green
• B. Flashing Amber
• C. Flashing Red
• D. Long Horn

Answer: (A)

Entering a lock with caution is signaled by flashing amber and green. The green part shows you’re allowed to move in, while the amber adds a cautionary note—you should slow down, be prepared for changing water levels or other traffic, and be ready to stop if the lock operator or other vessels require. The combination communicates a controlled entry with extra awareness. Flashing amber alone means exercise caution, but it doesn’t explicitly authorize entry. Flashing red means stop, and a long horn is an audible warning rather than a signal directing entry.

Entering a lock with caution is signaled by flashing amber and green. The green part shows you’re allowed to move in, while the amber adds a cautionary note—you should slow down, be prepared for changing water levels or other traffic, and be ready to stop if the lock operator or other vessels require. The combination communicates a controlled entry with extra awareness.

Flashing amber alone means exercise caution, but it doesn’t explicitly authorize entry. Flashing red means stop, and a long horn is an audible warning rather than a signal directing entry.