Unless extremely flexible wire rope is used, the sheave diameter should always be as large as possible, but should never be less than __________.

Correct Answer: Option B — 20 times the rope diameter

Standard seamanship practices dictate that sheave diameter must be at least 20 times the rope diameter to prevent excessive bending stress and fatigue on wire rope. Smaller diameters cause internal friction and wire deformation, significantly reducing the safe working load and service life of the wire rope assembly.