Final answer:
Member firms must submit reports to FINRA regarding customer complaints on a quarterly basis, as required by FINRA Rule 4530.
Step-by-step explanation:
The Financial Industry Regulatory Authority (FINRA) requires member firms to report customer complaint information regularly. Specifically, according to FINRA Rule 4530, member firms are required to report quarterly statistical and summary information regarding written customer complaints. Therefore, the correct answer is B) The past quarter.
Member firms must submit these reports no later than 15 days after the end of each calendar quarter. This ensures that FINRA can monitor and address potential issues in the market and with specific member firms timely. It is critical for member firms to stay compliant with these regulations to maintain their good standing with FINRA.