Beneath are my multiple choices questions to assess the students' abilities in file navigation by using "ls."

• novice vs. competent

Use "ls" to view the details of all visible files in a directory, including ownership, execution rights, size, modification dates.

1. ls -a
2. ls -F
3. ls -l
4. ls -s

• competent vs. expert

Use "ls" to view the details of all visible files in a directory, including ownership, execution rights, size (in human readable format), modification dates, and sort them by their modification dates (most recently modified file at the bottom).

1. ls -ahstr
2. ls -lHstr
3. ls -aHstr
4. ls -lhstr