What Is the Purpose of the Concept of "Separation of Duties

Multiple Choice

What is the purpose of the concept of "separation of duties" as used in some security models?

A) To allow multiple users to access the same file at the same to perform different file updates.
B) To allow system administrators to have powers that regular users do not.
C) To permit different user groups to have different levels of file access.
D) To prevent authorized users from making improper modifications to data.