Final answer:
The force exerted to move a crate across a floor is more than its weight.
Step-by-step explanation:
When a worker drags a crate across a floor, they need to exert a force greater than the force of friction between the crate and the floor in order to move it. The force required to move the crate depends on the coefficient of friction and the weight of the crate. If the crate weighs 150 pounds, the force needed to move it would be greater than 150 pounds, since friction opposes the motion. Therefore, the answer is C) More than 150 lb.