Which of the following is a prohibited purchase using the GPC?

The correct choice indicates that cash advances are a prohibited purchase using the Government Purchase Card (GPC). The rationale for this prohibition lies in the primary purpose of the GPC, which is to facilitate the acquisition of goods and services needed for official government business. Cash advances do not align with this purpose, as they do not provide a direct benefit to government operations that can be monitored and accounted for.

Cash advances can pose significant risks, such as insufficient tracking and oversight. They open potential avenues for misuse and fraud, as cash is more difficult to trace compared to transactions involving goods or services. Therefore, regulations surrounding the use of the GPC clearly prohibit cash advances to maintain the integrity of government purchasing and ensure accountability.

In contrast, the other options represent allowable expenditures under the GPC guidelines when properly justified. Supplies for official use can be purchased to support government operations. Airtime for government phones is necessary for official communication, and services under $200 are often permitted due to their lower risk and manageable accountability, provided they align with regulatory guidelines.