Final answer:
The act of a real estate agent receiving a $50 restaurant gift certificate from a mortgage broker is a violation of the Real Estate Settlement Procedures Act (RESPA) (option c), which prohibits kickbacks or rewards for referrals involving a federally related mortgage loan.
Step-by-step explanation:
The real estate agent receiving a $50 restaurant gift certificate from a mortgage broker for referring a home buyer is in violation of the Real Estate Settlement Procedures Act (RESPA). RESPA prohibits the giving or accepting of any fee, kickback, or thing of value pursuant to any agreement or understanding, oral or otherwise, that business incident to the real estate settlement service involving a federally related mortgage loan shall be referred to any person. In this scenario, the gift certificate can be considered a thing of value given as a token of appreciation for the referral, which makes it non-compliant with RESPA's regulations.