Q3. This question requires to use lower level system call read O and write O functions, read (input) only one byte at a time from the keyboard, and write (output) only one byte at a time to the screen. Modify the following program so that it prompts the user to enter an entire sentence, reads the sentence, then echoes the entire sentence. You'll need to use loops, of course. Int main(void) f char aLetter; write(STDOUT.FILENO, "Enter one character:", 21); // prompt user read(STDIN_FILENO, \&aLetter, 1); write(STDOUT_FLENO, "You entered: ", 13); write(STDOUTFFLENO, \&aLetter, 1); return 0