A compound X when treated with phthalic anhydride in presence of concentrated H₂SO₄, yields 'Y'.'Y' is used as an acid base indicator. "X" and "Y' are respectively
A Carbolic acid,Phenolphthalein
B Anisole, methyl orange
C Salicylaldehyde, Phenolphthalein
D Toludine, Phenolphthalein