9. A ball of mass m is connected by a string of length L to a pivot fixed in place. A. The ball is originally at rest. A force F applied horizontally to the right on the ball. The force barely balances the gravity and the string tension so that the ball has negligible kinetic energy when it slowly swings up. The string finally makes an angle θ with the vertical line. What is the work done by the force F during this process?

(A) mgL(sinθ)
(B) mgL(1-cosθ)
(C) mgL(cosθ-1)
(D) mgL(cosθ)

(E) 0

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