Tertiary sector (also known as service sector) is one that encompasses service activities and product trade.
The Tertiary Sector involves the provision of services to both other businesses and end consumers. These may be involved as transportation, sales and distribution of goods from producers to consumers; they may also be from other services not directly linked to the end product, such as pest control and entertainment. Goods can be transformed as well, as happens in a restaurant or an electronics. Thus, the focus is on interaction between people, providing a product or service that satisfies the desires of those who demanded it.
B, the potential energy is transformed into kinetic. It is not A, because energy can neither be destroyed or created. And I remember the difference between the energy types as the meaning of potential (not in use; not yet at full) and saying that it is not moving.
