The correct answer is C. Remediation and retesting.
ISACA guidance explains that penetration testing identifies exploitable weaknesses and provides guidance to address them. Once findings are identified, the next logical and control-appropriate step is to remediate the weaknesses and then retest to confirm they have been effectively resolved.
Option A is not the best next step because vulnerability scanning may supplement testing, but after a completed penetration test with findings, the priority is to fix what was found and verify closure.
Option B may be part of root cause work, but it is not the primary next step.
Option D is important from an information-handling perspective, but it does not address the control weaknesses identified by the test.
Therefore, the correct answer is C, because findings from a penetration test should drive remediation followed by retesting to validate that the identified weaknesses have been corrected.
References (Official ISACA):
* ISACA, The Future of Cybersecurity Assessments Is Here - VAPT identifies weaknesses and provides guidance to address them.
* ISACA, Taking a Risk-Based Approach to Pen Testing - findings should be evaluated and acted on according to business impact.
* ISACA, Smarter Testing Equals Safer Digital Experiences - findings should be assessed for exploitability and impact, supporting focused remediation.