To justify its ongoing security budget, which of the following would be of MOST use to the information security` department? 

Answer options:

A. Security breach frequency
B. Annualized loss expectancy (ALE)
C. Cost-benefit analysis
D. Peer group comparison

C

Cost-benefit analysis is the legitimate way to justify budget. The frequency of security breaches may assist the argument for budget but is not the key tool; it does not address the impact. Annualized loss expectancy (ALE) does not address the potential benefit of security investment. Peer group comparison would provide a good estimate for the necessary security budget but it would not take into account the specific needs of the organization.