Black-and-white camera film, in the old days of film photography, was very sensitive to blue light but not to red light. Blue skies would often show very little detail, because the film couldn't record all that it was seeing. To compensate, photographers would put a red filter on the lens, darkening the sky enough that the film could record its fluffy clouds.
This paragraph best supports the statement that
Choose one answer.
a. black-and-white photography used to be very popular.
b. blue filters cut out red light.
c. red filters cut out some blue light on black and white film.
d. red filters were very popular in the old days of photography.
e. infrared rays are invisible to the naked eye.