I _____ her voice at once on the phone, though we hadn't seen each other for ten years.

1. A.
   heard
2. B.
   knew
3. C.
   realized
4. D.
   recognized

I _____ her voice at once on the phone, though we hadn't seen each other for ten years.

A. heard    B. knew    C. realized    D. recognized

I _____ her voice at once on the phone, though we hadn't seen each other for ten years.

A. heard B. knew C. realized D. recognized

 I ______ her voice at once on the phone, though we hadn’t seen each other for ten years．

       A．heard                 B．knew                  C．realized               D．recognized