The correct answer is D. Necessity.
A necessity is a good or service that is required to support human life, needs and activities. Examples of necessities include food, water, shelter, clothing, and healthcare.
A producer product is a good or service that is used to create other goods or services. Examples of producer products include raw materials, machinery, and tools.
A consumer product is a good or service that is used by individuals for their own personal use. Examples of consumer products include food, clothing, and electronics.
A luxury is a good or service that is not essential to life but that is considered to be desirable. Examples of luxuries include expensive cars, jewelry, and vacations.