The correct answer is B) is approved by the Public Health Service. The reason this is the correct answer is that before taking drinking water on board in the U.S. or its possessions, the responsible person from the vessel should ensure that the water source is approved by the Public Health Service. This is a regulatory requirement to ensure the water is safe for consumption and meets the necessary sanitation standards. The other answer choices are not correct because: A) chlorination is just one method of treating water, but does not necessarily indicate the water source is approved; C) the source being from surface water does not automatically make it unsafe; and D) the fact that a city uses the water does not necessarily mean it has been approved by the Public Health Service.