Which is the best indicator for the titration of HCl solution with NaOH solution, i.e. the most nearly ideal one?
Acid Range Color pH Range Basic Range Color
a. pink 1.2-2.8 yellow
b. blue 3.4-4.6 yellow
c. yellow 6.5-7.8 purple
d. colorless 9.9-11.1 red
e. none of these indicators
Answer: C