Under the Natural Gas Act, the GPSC's role is primarily to:

The correct answer highlights the role of the Georgia Public Service Commission (GPSC) in promoting a competitive marketplace within the natural gas industry. The GPSC is tasked with overseeing the functioning of natural gas utilities, ensuring that the market operates fairly and efficiently. By supporting the development of a competitive marketplace, the GPSC aims to enhance consumer choice and foster conditions that can lead to better pricing and service options for consumers.

This approach contrasts with a focus on fixed pricing, regulated monopolies, or direct management of pricing, which could stifle competition and limit market dynamics. The emphasis on competition allows for innovation, improved service, and the potential for lower prices as various providers vie for consumer business, ultimately benefiting end-users in the natural gas market.