Which of the following is NOT a financial service firm overseen by the FCA?

Retail stores do not fall under the category of financial service firms overseen by the FCA. The FCA, or Financial Conduct Authority, is responsible for regulating financial services in the UK, which includes banks, insurers, and investment firms. These entities are involved in managing money, underwriting insurance, and facilitating investments, respectively, all of which are crucial for maintaining the stability and integrity of the financial system. Retail stores, on the other hand, primarily engage in selling goods and services to consumers and do not offer financial products or services that require regulation by the FCA. Hence, they do not come under the remit of the FCA's regulatory framework.