In conducting an appraisal of the economy and efficiency with which resources are employed, an internal auditor is responsible for:

The Answer Is (A)

answer ( A) is the correct answer 

a. Determining whether operating standards have been established

The answer is (A)

Management is responsible for setting operating standards to measure an activity's economical and efficient use of resources. internal auditors are responsible for determining whether:

1. Operating standards have been established for measuring economy and efficiency.
2. Established operating standards are understood and are being met.
3. Deviations from operating standards are identified, analyzed, and communicated to those responsible for corrective action.
4. Corrective action has been taken.

Options (a) and (c) should do the trick.