How long is the line and chafing chain mentioned in the text?

The correct choice indicates that there is a specific length of line and chafing chain used for certain marine operations, such as anchoring or towing. In this context, the details provided align with common practices in mariner guidelines where the lengths are established to ensure safety and functionality.

For many vessels, having a length of line that is adequate ensures that there is enough reach for various maneuvers while also considering the additional protection provided by chafing chains. The 100ft of line combined with 10ft of chafing chain creates a balance that allows for flexibility in working scenarios, avoiding unnecessary wear on the line due to abrasion against surfaces, which is what the chafing chain is designed to mitigate. This combination is practical and often recommended in training and operational contexts, making it a feasible standard for usage.

Understanding this combination contributes to operational safety and efficiency, which is crucial for any nautical activities.