The correct answer is A) Take action to permit safe passage. In this situation, Vessel "B" should take action to permit safe passage because it is the overtaking vessel in a narrow channel. According to the Inland Navigation Rules, the vessel that is overtaking another vessel in a narrow channel must take early and substantial action to permit safe passage. Vessel "A" has the right of way as the downbound vessel, so Vessel "B" must take the necessary steps to safely pass Vessel "A" without impeding its progress. The other answer choices are incorrect because B) initiating maneuvering signals is not the appropriate action for the overtaking vessel, C) Vessel "A" has the right of way as the downbound vessel, and D) some action must be taken by Vessel "B" to ensure safe passage.