Definition of Internal Control Weakness:Internal control weaknesses occur when controls fail to prevent or detect errors, fraud, or conflicts of interest. Allowing project managers to oversee companies in which they have a material interest introduces aconflict of interest, undermining internal controls.

Explanation of Answer Choices:

A. The contract department staff awards contracts and maintains a database for vendor information: While not ideal, this does not automatically signal a critical control weakness.

B. Management policy allows project managers to oversee controls of companies in which they have a material interest: Correct. This represents a serious conflict of interest and lack of independence.

C. The budget department staff is responsible for preparing the budget and for reporting on budget cost variances: This may indicate concentration of duties but is less severe than a direct conflict of interest.

D. The accounting department has one clerk prepare vendor payments and another clerk reconcile bank accounts: This demonstrates good segregation of duties, not a weakness.

References:

COSO,Internal Control - Integrated Framework.

GAO,Standards for Internal Control in the Federal Government (Green Book).