Which office is responsible for collecting and spending state funds in Missouri?

The correct choice, which identifies the office responsible for collecting and spending state funds in Missouri, is the Missouri Treasurer. This role specifically entails managing the state's finances, including the receipt and disbursement of funds. The Treasurer oversees the state’s bank accounts, invests state funds, and ensures the sound fiscal management of public money.

The Missouri Auditor, while related to financial duties, primarily focuses on auditing state agencies and ensuring accountability and transparency in the use of state resources rather than directly managing funds. The Secretary of State's responsibilities encompass various administrative tasks, such as overseeing elections and maintaining state records, which do not include the management of state funds. The Attorney General serves as the chief legal officer for the state and handles legal affairs, providing counsel and representation rather than financial management.

Thus, the Treasurer's role is crucial in maintaining the financial health of the state, making it the appropriate answer to the question.