Question

the box is at rest on the table. which force is represented by vector a?
☐ sliding friction
☐ rolling friction
☐ static friction
☐ fluid friction

Explanation:

The box is at rest, so the force opposing the applied pulling force $F_p$ must be a friction force that acts on stationary objects. Sliding friction acts on moving sliding objects, rolling friction acts on rolling objects, and fluid friction acts on objects in fluids. Static friction is the friction that keeps stationary objects from moving when a force is applied.

Answer:

static friction