The correct answer is D) imparts energy to a fluid to move it from point "A" to point "B". A pump is defined as a device that imparts energy to a fluid, such as a liquid or gas, in order to move it from one location (point "A") to another (point "B"). This is the fundamental function of a pump - to provide the necessary energy to transport the fluid through a system. The other answer options are incorrect because they do not fully capture the definition of a pump. Option A) describes a general function of a pump but does not cover the full definition. Option B) is incorrect as not all pumps create a vacuum to move liquids. Option C) is also incomplete as it only describes part of the pump's function in creating a pressure differential.