Using vi， you want to save changes to the file myfile with ：w!， but vi complains it cannot write to the file. Therefore， you want to check the write permissions on the file. To do this without leaving vi， you type：（）

• A、 ：!ls-I myfile
• B、 ：/ls-l myfile
• C、 esc ：Is -I myfile
• D、 ：？ls-l myfile