Unix

Answer : D

Explanation :
We can use the command chmod 711 noname, followed by chmod u+s noname (use
ls -1 noname and check). Else use the single command chmod 4711 noname. What is this "s" anyway? Only the super user has the permission to change /etc/ passwd file. But any user can update it through the passwd (bin/passwd) command. If you type ls-l /bin/passwd you can see the user execution bit set to s instead of x). It is because of this "s". a user can access /etc/passwd through the passwd command, for which he is not otherwise entitled to