What type of file permissions can be altered in a Linux system?

In a Linux system, file permissions can be categorized predominantly into three types: read, write, and execute. This trinity of permissions controls the accessibility and the actions that can be performed on files and directories.

Read permission allows a user to view the content of a file. Write permission enables a user to modify or delete the file. Execute permission permits a user to run a file as a program or script.

The ability to alter these permissions is essential for managing file access and maintaining security within the system. Users with appropriate privileges, typically the file owner or a superuser, can use commands such as chmod to change these permissions as needed.

The other options provided only focus on a subset of these permissions, which limits the understanding of what can actually be modified in a Linux environment. For example, stating that only read and write permissions can be altered overlooks the critical execute permission necessary for comprehensive file handling.