Answer:
First, we need to understand the definition of primary industry and secondary activity:
- Primary industry refers to a type of industry that obtains raw materials from the environment and transform them into finished goods.
- Secondary activity refers to additional activity that conducted by the company outside of their main operation.
Agriculture sectors have both of these characteristics
It's considered a primary industry because it transform crops (raw materials) into consumable foods (finished goods).
Agriculture can have secondary activities because companies in agriculture often have some sort of left-over material that they can use to create other type of products beside their main operation. For example, producer of banana often sell the leaves and branches of the tree to other companies that can create art using those as materials.