The medicine is supposed to cure this disease, but I’m not sure it       .

1. A.
   does
2. B.
   was
3. C.
   has
4. D.
   is

The medicine is supposed to cure this disease, but I’m not sure it        .

    A. does           B. was           C. has              D. is

The medicine is supposed to cure this disease, but I'm not sure it ________.

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