Final answer:
The security control focused on preventing collusion is Separation of duties. This approach spreads tasks and privileges among individuals to reduce the risk of conspiracy to commit a fraudulent act.
Step-by-step explanation:
The security control that is directly focused on preventing collusion is C. Separation of duties. This principle involves dividing tasks and privileges among multiple people to reduce the risk of fraudulent activities because it is unlikely that two or more individuals will conspire to commit a wrongful act. For example, in financial scenarios, one employee might be tasked with recording transactions, while another is responsible for authorizing payments. This division makes it more difficult for a single individual to commit fraud without being detected by others.
Collusion is a fraudulent activity that involves two or more individuals working together, and separation of duties is designed specifically to impede such collaborations. Other options like Principle of least privilege or Job descriptions are important security measures too but they are not as focused on preventing collusion as separation of duties is. Likewise, Qualitative risk analysis helps identify risks but does not directly prevent collusion.