17. A patient accusing a doctor of malpractice will find it difficult to prove damage if there is a lack of some other doctor to testify about proper medical procedures.
(A) if there is a lack of some other doctor to testify
(B) unless there will be another doctor to testify
(C) without another doctor’s testimony
(D) should there be no testimony from some other doctor
(E) lacking another doctor to testify


OA is C

Why isn't it B?