A fundamental component of internal control is the separation of duties for high-risk transactions. The underlying separation of duties concept is that no individual should be able to execute a high-risk transaction, conceal errors, or commit fraud in the normal course of their duties.
You can apply separation of duties at either a transactional or an organizational level. For example, payroll has access to employee financial records, but only payroll managers can approve raises.
Answer the following question(s):

How do you define a high-risk transaction?
If you were a security professional in a company, what are four roles (two sets of two related roles) you would separate and why? Provide examples not mentioned in the description for this discussion.

Fully address the questions in this discussion; provide valid rationale for your choices, where applicable;