The correct answer is C. A scientist
Explanation:
A reliable source refers to one source that can be trusted, in terms of people, a person is considered as a reliable information source when he or she is an expert or authority in the field and therefore his or her words are valid. In the case of "Taking a short shower instead of a bath saves about 40 gallons of water" the one that would be the most reliable source of this information is a scientist, because this is the only professional that can effectively prove the amount of water that is saved and provide arguments to explain this based on science. Also, different from a farmer, politician or meteorologist a scientist is related to numbers and the scientific method that can be used to prove or disprove a statement like the one presented.
