In the context of the problem, the expression \( -16t^2 + 32t + 47 \) represents the height of the football at any time \( t \) seconds after it is thrown. The term \( 47 \) in the expression indicates the initial height from which the football is thrown, which is 47 feet above the ground.
Therefore, the correct interpretation is:
47 represents the height of the football when the quarterback throws it.