BOTH INTERNATIONAL & INLAND A vessel may exhibit lights other than those prescribed by the Rules as long as the additional lights comply with which requirement(s)?

Correct Answer: Option C — do not interfere with the keeping of a proper look-out

Rule 20(b) permits the display of additional lights or sound signals provided they cannot be mistaken for the lights or signals specified in the Rules. Crucially, these additional signals must not impair the visibility or distinctive character of the prescribed lights or interfere with the keeping of a proper look-out.