You are downbound on the Ohio River locking through Greenup. The chamber has been emptied and the lower gates are open. You hear one short blast of the whistle from the lock. You should __________.

Correct Answer: Option D — leave the lock

In accordance with the Inland Navigation Rules and specific lock operating procedures for the Ohio River, one short blast from the lockmaster is the standard signal indicating that the lock is ready and the vessel is cleared to depart the chamber. Proceeding immediately is required to maintain traffic flow.