—Would you have come to his help, had you been free?

 —Yes. But I______ engaged.

　A. was B. were C. had been D. would be

—Would you have come to his help, had you been free?

—Yes. But I______ engaged.

1. A.
   was
2. B.
   were
3. C.
   hadbeen
4. D.
   wouldbe