The -a option is used to display hidden files and directories in a command-line interface. Hidden files and directories are those that start with a dot (.) and are normally not shown by default. The -a option stands for "all" and shows all files and directories, including the hidden ones. The -a option can be used with commands such as ls, dir, or find to list or search for hidden files and directories. The -s, -lh, and -t options are not used to display hidden files and directories. The -s option stands for "size" and shows the size of files or directories in bytes. The -lh option stands for "long human-readable" and shows the size of files or directories in a more readable format, such as KB, MB, or GB. The -t option stands for "time" and sorts the files or directories by modification time. Reference:
Official CompTIA learning resources CompTIA A+ Core 1 and Core 2, page 17 CompTIA A+ Complete Study Guide: Core 1 Exam 220-1101 and Core 2 Exam ..., page 107