A contractor's umbrella or excess liability policy is designed to:

解析

An umbrella or excess policy sits above scheduled underlying policies — commercial general liability, commercial auto, often employers' liability — and pays only after those limits are exhausted, which is how a contractor reaches catastrophic-claim limits without buying them at the primary layer. (c) inverts that structure. (a) confuses liability limits with workers' compensation, which is statutory, separate, and not something an umbrella replaces. (d) names the risk the CGL's 'your work' exclusion leaves with the contractor, and an umbrella follows the underlying policy's terms rather than curing its exclusions.