In Linux, which statement about permission bits is accurate?

In Linux, which statement about permission bits is accurate?

• A. Read, Write, Execute; two categories: user and others.
• B. Read, Write, Execute; two categories: group and others.
• C. Read, Write, Execute; two categories: user and group.
• D. Read, Write, Execute; three categories: user, group, and others.

Answer: (D)

The key idea is that Linux permission bits are defined for three user classes: the file’s owner (user), the file’s group, and everyone else (others). For each of these classes there are three permissions you can grant or deny: read, write, and execute. That’s why the accurate statement describes three categories: user, group, and others, each with Read, Write, and Execute. This matches how the permission string shown in listings is organized (for example, rwxr-xr-- splits into owner permissions, then group permissions, then others). The execute bit matters for running programs or scripts, while read and write control viewing and modifying content. Other choices are missing a category or pair categories that don’t cover all three groups, which is why they aren’t correct.

The key idea is that Linux permission bits are defined for three user classes: the file’s owner (user), the file’s group, and everyone else (others). For each of these classes there are three permissions you can grant or deny: read, write, and execute. That’s why the accurate statement describes three categories: user, group, and others, each with Read, Write, and Execute.

This matches how the permission string shown in listings is organized (for example, rwxr-xr-- splits into owner permissions, then group permissions, then others). The execute bit matters for running programs or scripts, while read and write control viewing and modifying content.

Other choices are missing a category or pair categories that don’t cover all three groups, which is why they aren’t correct.