Each of the following quality control policies and procedures is typical of ones that can be found in public accounting firms' systems of quality control. Identify each of them with one of the six elements of quality control.

1. Assign management responsibilities in such a manner that commercial considerations do not override the quality of work performed.
2. Establish policies and procedures for resolving differences of opinion among firm personnel that arise during professional engagements.
3. Develop policies and procedures to ensure that professionals are provided appropriate professional development opportunities.
4. Review engagement documentation, reports, and the client's financial statements.
5. Develop effective performance evaluation, compensation, and advancement procedures.
6. Identify circumstances and relationships that create threats to independence and take appropriate action to eliminate those threats or reduce them to an acceptable level.
7. Identify whether the firm possesses the competency, capability, and resources to appropriately serve a specific client.
8. Devote sufficient resources to develop, communicate, and support the firm's quality control procedures.
9. Retain engagement documentation for a sufficient period of time to satisfy the needs of the firm, professional standards, laws, and regulations.