What is the arrangement of a shaft tunnel as fitted on a single-screw vessel?

Correct Answer: Option C — The shaft tunnel is offset from centerline of the vessel with a walkway positioned on one side of the shaft any piping runs carried underneath the walkway.

In single-screw vessels, the shaft tunnel is typically offset from the centerline to accommodate the shaft and provide a dedicated walkway on one side. Piping runs are routed underneath this walkway to protect them from mechanical damage and to maintain clear access for inspection and maintenance.