Which of the following is one of the ID cards issued by the Military?

The Common Access Card (CAC) is the primary identification card issued by the U.S. Department of Defense for active-duty members of the military, Reserve and National Guard members, and eligible contractor personnel. It serves as a multi-purpose smart card that provides access to military installations, systems, and services, including secure networks. Additionally, the CAC can facilitate various transactions within the military community and provides a secure method of authenticating individuals for identity verification purposes.

In contrast, the other options listed do not serve as military-issued identification. The Employee ID Card typically pertains to civilian employees and may not be recognized as a military ID. A Driver's License is a state-issued document for operating vehicles and does not carry military-specific credentials. A Social Security Card is primarily for tax purposes and identifying individuals within the Social Security system, lacking any military identification function. Thus, the CAC stands out as the correct answer due to its specific purpose and usage within the military context.