Which description best fits the external bow thruster described as cheapest and easiest to install?

• A. External bow thrusters bolt to the hull and are easy to install on small boats, not requiring major bow modifications, but they create drag when deployed.
• B. Tunnel bow thrusters require hollowing out the bow and significant hull modification.
• C. In-hull units are installed inside the hull and do not protrude.
• D. Outboard motors are used only for propulsion, not as thrusters.

Answer: (A)