What is necessary before granting a security clearance?

A thorough background investigation is essential before granting a security clearance because it assesses an individual's loyalty, trustworthiness, and reliability in handling sensitive information. This investigation typically includes checking criminal records, credit history, previous employment verification, and references. The aim is to ensure that the applicant does not pose a security risk and is suitable for access to classified materials.

Each component of the background investigation is crucial in informing security personnel about the potential risks associated with the applicant. This process helps maintain national security and protects sensitive information from being compromised. While the other options may contribute to an overall understanding of an individual's qualifications, they do not hold the same level of importance as the comprehensive background investigation required for security clearance.