Which statement describes when a sailboat is considered a power-driven boat?

• A. A sailboat becomes power-driven only when sails are removed.
• B. A sailboat is never considered power-driven.
• C. A sailboat becomes power-driven when a motor is used to move it, an outboard or inboard.
• D. When a motor is used to move a sailboat, outboard or inboard, it is considered a power-driven boat.

Answer: (D)