Why is a strawberry an accessory aggregate fruit?

A strawberry is classified as an accessory aggregate fruit because of how it develops from a single flower and which parts of the plant contribute to its structure.

• Aggregate Fruit: A strawberry is considered an aggregate fruit because it forms from a single flower that contains many separate and distinct pistils. Each of these pistils develops into a tiny, individual fruit known as an achene—the small, brown "seeds" visible on the surface of the strawberry.1
• Accessory Fruit: It is defined as an accessory fruit because parts other than the ripened ovary participate in its formation. In the case of a strawberry, the fleshy, edible portion is actually a much-swollen receptacle—the tip of the flower stalk that bears the flower parts—rather than the ovary tissue itself.21

By combining these characteristics, the strawberry is botanically categorized as an aggregate of achenes borne on a fleshy, accessory receptacle.1