Final answer:
The security officer is typically responsible for the security of IT resources, reporting to the CIO, who has ultimate accountability within an organization.
Step-by-step explanation:
The individual with the responsibility to ensure the security of all IT resources can vary across organizations, but typically, it's the security officer who is directly responsible. The Chief Information Officer (CIO) often has the ultimate accountability for the security of IT resources in an organization, as they oversee the IT department and its various functions, including security. The security officer would report to the CIO and focus specifically on the development, enforcement, and updating of security policies. A steering committee may have an oversight role, but not direct responsibility, and a systems development manager would be more focused on the development of systems rather than their ongoing security.