Due professional care is the care and skill expected of a reasonably prudent and competent internal auditor2. It requires internal auditors to follow the International Professional Practices Framework (IPPF) issued by the Institute of Internal Auditors (IIA), which includes the Code of Ethics and the Standards3. One of the aspects of due professional care is to perform risk-based audits, which means identifying and assessing the risks that may affect the organization's objectives, and designing and executing audit procedures that provide reasonable assurance on the effectiveness of risk management and internal control4. Therefore, option C is an appropriate statement to demonstrate how a small internal audit activity with limited resources can demonstrate due professional care by ensuring adequate focus on the most significant risks and areas.
References:
1: CIA Exam Practice Questions - Certified Internal Auditor 2019
2: Due professional care definition
3: What is due professional care in internal audit?
4: Standard 1220 - Due Professional Care - The Institute of Internal Auditors or The IIA