What is the minimum size mirror required while pulling a skier on a PWC?

The correct answer identifies that a mirror of a minimum size of 4 inches by 4 inches is required while pulling a skier on a Personal Watercraft (PWC). This specification is vital for ensuring safety on the water, as the mirror allows the operator to maintain visibility of the skier in tow without having to turn around, which could lead to a loss of control and an increased risk of accidents.

A mirror of this size ensures that the operator can effectively monitor the skier's position and movements, helping to respond promptly to any changes or signals. The regulations focus on providing adequate sight lines for safety, as larger mirrors enhance visibility but a minimum size has been established to ensure a baseline standard for all operators.

Other size options listed do not meet the regulatory requirements set for PWC operation and skier safety, as either they do not provide enough surface area for adequate viewing or exceed the requirements without necessity. Therefore, the 4 by 4 size strikes a balance between safety and practicality as per the established regulations.