---How can I wake up so early?

---Set the alarm clock, ______ you will make it.

1. A.
   but
2. B.
   or
3. C.
   and
4. D.
   so

－How can I wake up so early?   

－Set the alarm clock，      you will make it．

A．But                      B．or                        C．and                      D．so