BOTH INTERNATIONAL & INLAND A power-driven vessel making way through the water sounds a fog signal of __________.

Correct Answer: Option D — one prolonged blast at intervals of not more than two minutes

Under Inland Navigation Rules, for the condition where 'A power-driven vessel making way through the water sounds a fog signal of', the correct requirement is: 'one prolonged blast at intervals of not more than two minutes'. This standard ensures clear navigational intent and collision avoidance.