Final answer:
The homeowner must receive a signed copy of the contract prior to work starting. It records the agreement between the parties involved, and it's beneficial for the contractor and subcontractor to have copies as well.
Step-by-step explanation:
The party that must receive a signed copy of the contract prior to work starting is b) the homeowner. This is essential as it serves as a formal agreement that all parties have consented to the terms and conditions of the work to be done. It protects everyone involved, providing a clear reference for the scope of work, payment schedules, and other important terms. In addition, it's beneficial for both a) the contractor and b) the subcontractor to have signed copies for their records to ensure they understand their responsibilities and can refer back to the contract in case of disputes or for any clarifications. While not typically a requirement, a signed copy of the contract might also be shared with d) the insurance company, especially if it's related to an insurance claim or to ensure coverage is in place based on the agreed work.