Q: In this task, you are given a context and four options. Each option is a suggested ending for the context. You should read the context and pick the best ending for the context. Please answer with "A", "B", "C", and "D". 
A picture of a man is shown and then drawings of human vertebrae. the man in gray out <sep> (A) places his spare leg on the shoulder hole of a carved metal object and begins to attach the second arm of the device, some gears are then shown and a device is held in his hand. (B) comes back in and shows a bedroom. (C) puts the skin back together and then looks at his work and smiles. (D) is standing in a room and started to rotate his hands forward and backward.
A:
D