Acid-Base Indicators Need to Have Very Intense Colors So That

Acid-base indicators need to have very intense colors so that a very low concentration is visible. Could there be a problem in using too much indicator?

A) No, the colors would just be darker.
B) No, indicators are inert.
C) Yes, more indicator requires more extreme pH values to change color.
D) Yes, the indicator could affect the acid-base chemistry being measured.
E) No, the colors would just be sharper.