Which scenario involves kinetic energy transforming into potential energy? A. a book lying on a shelf B. a train traveling at a constant speed C. a person drawing back the string of a bow and arrow D. a ball beginning to descend after being thrown upward

The answer is C.

The Kinetic energy which was exerted and experience pulling the string of a bow is kept as a potential energy at the end of the arrow in contact with the string. Once release from aim at stationary position the potential energy is again transformed.