--- Do you know who designed the CD-ROM Around the World in Eight Hours?
--- Yes. It ______ by Nancy Jackson.

--- Do you know who designed the CD-ROM Around the World in Eight Hours?

--- Yes. It ______ by Nancy Jackson.

A．has designed       B．designed          C．designs           D．was designed

--- Do you know who designed the CD-ROM Around the World in Eight Hours?
--- Yes. It ______ by Nancy Jackson.

1. A.
   has designed
2. B.
   designed
3. C.
   designs
4. D.
   was designed