TOEFL Listening: ETS-TOEFL听力机经 - 3ZPQML95UQ23U1P9P$

What does the professor imply about the historical record of the early days of photography? A. It is incomplete. B. It was sometimes falsified by inventors. C. It was written mostly by people who had little knowledge of photography. D. It is more detailed than most other historical records from that time period.