BOTH INTERNATIONAL & INLAND If you are approaching a bend, and hear a whistle signal of one prolonged blast from around the bend, you should answer with a signal of __________.

Correct Answer: Option A — a prolonged blast

Under Inland Navigation Rules, for the condition where 'If you are approaching a bend, and hear a whistle signal of one prolonged blast from around the bend, you should answer with a signal of', the correct requirement is: 'a prolonged blast'. This standard ensures clear navigational intent and collision avoidance.