The correct answer is: A. cat emp[!0-9]
The command cat is used to concatenate files. The square brackets [ ] are used to specify a range of characters. The exclamation mark (!) is used to negate a range of characters. So, the command cat emp[!0-9] will concatenate all files beginning with the string ’emp’ and followed by a non-numeric character.
The command more is used to display a file one page at a time. The command emp[x-z] will display all files beginning with the string ’emp’ and followed by a character in the range ‘x’ to ‘z’. The command emp[a-z] will display all files beginning with the string ’emp’ and followed by a character in the range ‘a’ to ‘z’.
The command cat emp[!0-9] is the only command that will concatenate all files beginning with the string ’emp’ and followed by a non-numeric character.