A golfer starts with the club over her head and swings it to reach maximum speed as it contacts the ball. Halfway through her swing, when the golf club is parallel to the ground, does the acceleration vector of the club head point straight down, parallel to the ground, approximately toward the golfer's shoulders, approximately toward the golfer's feet, or toward a point above the golfer's head?
A. Parallel to the ground, approximately toward the golfer's shoulders
B. Straight down
C. Approximately toward the golfer's feet
D. Toward a point above the golfer's head