What is the function of following UNIX command?WC – l < a >b&

• A. It runs the word count program to count the number of lines in its input, a, writing the result to b, as a foreground process.
• B. It runs the word count program to count the number of lines in its input, a, writing the result to b, but does it in the background.
• C. It counts the errors during the execution of a process, a, and puts the result in process b.
• D. It copies the ‘ l ’ numbers of lines of program from file, a, and stores in file b.