An access control system that grants users only those rights necessary for them to perform their work is operating on which security principle?

The correct answer is A) Least Privilege

Explanation:

In terms of Computer Security, least privilege is granted to someone who has enough access to work on the system as usual but cannot edit or work on other

This is stark contrast to other privileges such as 'Mandatory Access' and 'Separation of Duties'

Least privilege as the name suggests, provides minimum access to a system, just enough for the user to smoothly carry out a task.

Separation of Duties e. g. is a different set of access rights and is used when more than one people need to work together to complete a task, but both users have access to different parts of the system.

These 'access controls' are generally developed to minimize corruption and chances of fraud within an organisation. Apart from that, especially in critical situations, it might also simply be necessary for only one person to access important controls at any given time, as a junior supervisor/engineer might be experienced enough to carry out the task properly.