Which command is used to make all files and sub-directories in the directory (prog)executable by all users?

Which command is used to make all files and sub-directories in the dir

1.	Which command is used to make all files and sub-directories in the directory (prog)executable by all users?
A.	chmod –R a+xprogs
B.	chmod –x a+xprogs
C.	chmod -1 a+xprogs
D.	chmod –R 222 progs
Answer» B. chmod –x a+xprogs