Question 320Navigation General

The correct answer is A) Five short blasts. When approaching a drawbridge during a scheduled closure period, you should sound five short blasts on the whistle or horn to indicate that you are requesting the bridge to open. This signal is specified in the U.S. Coast Guard Navigation Rules and Regulations, which provide the standardized sound signals for vessels. The other answer choices are incorrect because they do not match the required signal for requesting a drawbridge opening during a closure period. Three prolonged blasts, two prolonged and two short blasts, and three short blasts followed by two prolonged blasts have different meanings and are used for other navigation situations, not specifically for requesting a drawbridge opening.