Which of the following commands can be used to convert all lowercase letters of a...

You can use the tr command to convert all lowercase letters of a text file to uppercase. The tr

command is used to translate, squeeze, and/or delete characters from standard input, writing to standard output. If you want to change all lowercase letters to uppercase, you will use the tr

[a-z] [A-Z] command.

Answer options B, A, and D are incorrect. The cat, tac, and less commands are used to display the output of the text file on the screen. These commands cannot translate the text from one form to another.