Which of the following describes Critical Infrastructure (CI)?

The definition of Critical Infrastructure (CI) refers primarily to systems and assets that are vital for the functioning of a society and economy, particularly in regard to national security, public safety, and health. The correct choice highlights that the loss of these systems could significantly impair national security. For instance, critical infrastructure encompasses areas such as energy supply, transportation systems, and water treatment, all of which are essential for sustaining the operational capabilities of a nation.

Other options do not accurately reflect the definition of critical infrastructure. For example, while marketing advantages or social media infrastructures may be important in a business context, they do not meet the criteria for systems that, if disrupted, would threaten national security or public welfare. Similarly, facilities for employee training, while they support organizational effectiveness, do not qualify as critical infrastructure on the national level. In essence, the emphasis on national security and the critical nature of these systems makes the correct choice clear.