Question 24

The permissions set on a regular file modified with chmod 654 file.txt are d-rwx-r--.

The command `chmod 654 file.txt` sets the file permissions to `rwxr-xr--`. This corresponds to the owner having read, write, and execute permissions (represented by `rwx`), the group having read and execute permissions (represented by `r-x`), and others having only read permission (represented by `r--`).

A) drw-r-xr--

This option is incorrect because it suggests that the file is a directory (indicated by the `d` at the beginning), which is not the case for a regular file. The permissions do not match the output of the `chmod 654` command.

B) d-rwx-r--

This option is incorrect because, like option A, it indicates that the file is a directory (due to the `d`), while `file.txt` is specified as a regular file. The permissions also do not correctly reflect those set by `chmod 654`.

C) --wxr-x-x

This option is incorrect because it shows that the owner has write and execute permissions but lacks read permission, which contradicts the permissions set by `chmod 654`. Additionally, it does not represent the correct structure of permissions for the file type.

D) rwx---r-x

This option is incorrect because it suggests that the owner has read, write, and execute permissions, which is accurate, but the group and others' permissions do not match the settings from `chmod 654`. The group is missing the execute permission, which should be present.

E) --r--r---

This option is incorrect because it only grants read permission to the owner and others, with no write or execute permissions, which does not align with the permissions set by `chmod 654`.

Conclusion

Option B is definitively correct as it accurately reflects the permissions assigned to the file by the `chmod 654` command, showing that the owner has read, write, and execute permissions, the group has read and execute permissions, and others have read permissions. All other options fail to represent the correct permissions or incorrectly indicate the file type.