Final Answer:
For creating a flat-bottomed hole in a piece of lumber, the appropriate tool is a Forstner bit, making Option B the correct choice.
Step-by-step explanation:
A Forstner bit (Option B) is designed for drilling flat-bottomed holes with clean and precise edges in woodworking. It excels at creating holes of various diameters and depths, making it suitable for tasks like drilling holes for dowels or creating recesses for hardware installation.
In contrast, a spade bit (Option A) tends to create holes with a rougher finish, a hole saw (Option C) is better for cutting large-diameter holes, and an auger bit (Option D) is more suitable for deep holes in wood. Therefore, for a flat-bottomed hole, a Forstner bit is the most appropriate choice.
Option B is the answer.