Final answer:
Active duty service members receive a Common Access Card (CAC) for identification and access to various services and facilities within the Department of Defense.
Step-by-step explanation:
Active duty uniformed service personnel are issued a Common Access Card (CAC) to be used for standard identification. The CAC is a multifunctional smart card that provides a variety of functions and services to its users in the Department of Defense (DoD). Not only does it serve as identification, but it also enables access to controlled spaces, computer networks, and proves a service member's eligibility for government services.