Which FAR part provides guidance on cost principles for governmental contracts?

The correct choice is based on the specific focus of the FAR on cost principles applicable to government contracts. Part 31 of the FAR outlines the principles for determining allowable costs for contracts with the federal government. This part provides detailed guidance on various cost elements, including direct and indirect costs, and offers criteria for billing, accounting, and reporting costs associated with government contracts.

This framework is crucial for both contractors and government agencies to ensure that costs are reasonable, allowable, and allocable according to federal standards. The focus on cost principles in Part 31 helps to maintain transparency and accountability in the use of federal funds.

Other parts mentioned, such as Part 10 (Market Research), Part 15 (Contracting by Negotiation), and Part 37 (Service Contracting), serve different purposes. While they are important within the overall contracting process, they do not specifically address cost principles, which is why Part 31 specifically provides the necessary guidance in that area.