What must occur before John's background investigation can be adjudicated if a potential issue has been flagged?

Before adjudicating John's background investigation, an Expandable Focused Investigation (EFI) is necessary if a potential issue has been flagged. An EFI is designed to gather more in-depth information about specific areas of concern that have arisen during the preliminary investigations. This process allows for a thorough examination of any potential risks linked to the individual, ensuring that all aspects of their background are comprehensively assessed.

Conducting an EFI is particularly important because it addresses any ambiguities and allows security personnel to make informed decisions regarding a candidate's suitability for the role in question. Thorough investigations can lead to a clearer understanding of the flagged issues, which is essential when determining an individual's eligibility for security clearance or access to sensitive information.

The other options would not sufficiently address specific concerns that have been identified, as they do not focus on tailored investigation processes that delve deeper into specific flagged issues.