Which of the following best defines availability in a cyber security context?

In the context of cyber security, availability refers to ensuring that information and resources are accessible to authorized users whenever they need them. This concept is a core principle of the CIA triad—Confidentiality, Integrity, and Availability—which is foundational in the field of information security. Guaranteeing access not only implies that data is accessible but also emphasizes the preservation of operational functionality in systems and networks, even in the face of failures or attacks. This makes option B the most suitable choice, as it encompasses the critical aspect of ensuring continuous access to important data and services.

The other options, while relevant to different aspects of cyber security, do not capture the essence of availability as succinctly. For example, securely storing data emphasizes protection and confidentiality, tracking mechanisms focus on monitoring and accounting for data usage, and building firewalls primarily relates to preventing unauthorized access rather than ensuring that data is always accessible to those who need it. Thus, option B stands out as the best definition of availability in the cyber security context.