Question 16 GLI03 - Master-LT 500-1600 GRT

The Correct Answer is C 1. **Why option C ("navigating in or near an area of restricted visibility") is correct:** The International Regulations for Preventing Collisions at Sea (COLREGs), specifically Rule 35 (Sound Signals in Restricted Visibility) and Rule 19 (Conduct of Vessels in Restricted Visibility), apply universally to all vessels (both international and inland, as the question states) whenever they are operating **in or near an area of restricted visibility**. This is a mandatory safety requirement designed to ensure that vessels take precautionary measures before entering poor visibility conditions and while operating within them, regardless of whether they can currently see other vessels or what equipment they possess. 2. **Why the other options are incorrect:** * **A) only if they have operational radar:** This is incorrect. While radar is a critical tool for navigation in restricted visibility (and Rule 19 requires proper use of radar if installed), the rules apply to *all* vessels, even those without radar. A non-radar-equipped vessel must still follow the rules regarding speed, fog signals, and prudent seamanship. * **B) in sight of one another in fog:** This is incorrect. If vessels are "in sight of one another," they would transition from the rules for restricted visibility (Rule 19) to the rules for vessels in sight of one another (Rules 11-18, the steering and sailing rules). Furthermore, the specific rules for restricted visibility (like mandatory fog signals) apply when they are *not* in sight of one another, necessitating precautionary action. * **D) only if they are showing special purpose lights:** This is incorrect. Special purpose lights (such as lights for towing, fishing, dredging, etc.) indicate a vessel's status or operation, but the application of the restricted visibility rules (like using fog horns or reducing speed) depends solely on the condition of visibility, not the vessel's operational status or lighting configuration.