Which statement best uses the term as defined in definition #2?

Word: staple, n or v

1. small metal fastener

2. necessary object

3. a basic ingredient in a recipe

4. a fiber or wool, cotton, or other cloth

a. The student didn't use a staple, so the pages of her report were very disorganized.

b. Staples are a staple in any teacher's desk.

c. All-purpose flour, sugar, baking soda, and baking powder are staples in every quality cookie dough.

d. It takes many wool staples to form a single fleece.