Answer:
D. They are intangible in nature
Explanation:
Service
Services are defined as valuable actions, deeds or effort performed in order to satisfy a consumer's or customer's needs.
It is an intangible product as opposed to goods which are tangible. Services includes banking, education, cleaning, insurance, land scaping, medical treatment and so on. Services are non physical, meaning they cannot be manufactured, transported or stored/stocked (that is, it cannot be stored for future uses).