---Can I help you, sir?

---No, thanks. I _____ around．

A．have just looked                                  B．have just been looking 

C．am just looking                                  D．just look

 ---Can I help you, sir?

   ---No, thanks．I _____ around．

       A．have just looked                                  B．have just been looking 

       C．am just looking                                  D．just look