Answer: The Answer is D.
Explanation: Butter consists of butterfat, milk proteins and water, and often added salt. Most frequently made from cow's milk, butter can also be manufactured from the milk of other mammals, including sheep, goats, buffalo, and yaks.
Theory because a theory has to be backed up by several experiments
School is an example like you have a load of work and its hard and u keep going cuz u know it will get you someone good adn another is running a marothon even though its hard you just keep going. hope this helps and please rate below :)
