Adita lifts a book from the floor, carries it across the room, and places it on a high shelf. when is adita doing work on the book?

a) she does work on the book at no time during this process.
b) she does work only while she carries the book across the room.
c) she does work from the moment she touches the book until she lets it go.
d) she does work as she picks up the book and as she lifts it to the shelf.