Why is access control necessary for files within an operating system?

Access control is essential within an operating system for several reasons, all contributing to the overall security and integrity of the system and its files.

Firstly, implementing access controls helps prevent malicious users from accessing personal files. This is important because unauthorized access can lead to data breaches, identity theft, or other forms of exploitation. Protecting sensitive information is crucial in maintaining user confidentiality and trust.

Secondly, ensuring that malicious users cannot modify others' files is another vital aspect of access control. Modifications to files without permission can compromise the integrity of data and lead to a loss of functionality or reliability. File integrity is paramount for system stability and for preserving the authenticity of information.

Finally, guarding against the potential sale of another user's personal data is a critical reason for having access controls in place. Personal data is valuable, and unauthorized access can result in not only privacy violations but also financial repercussions for individuals and organizations.

Consequently, all these reasons interlink to emphasize that access control mechanisms are foundational in safeguarding data and maintaining a secure operating environment. By preventing unauthorized access, modifications, and misuse of personal data, access control serves multiple protective roles, thus justifying the selection of all the above options as essential functions of access control.