Phenolphthalein is used as an indicator for the titration of sodium hydroxide solution against a standard solution of oxalic acid. The colour change that is observed at an alkaline pH close to the equivalence point during this titration is:

1. A. Pink to colourless
2. B. Pinkish red to yellow
3. C. Colourless to pink
4. D. Yellow to pinkish red

Attempt this NEET 2026 Chemistry question free — pick an option to reveal the correct answer and a step-by-step explanation. Then join NEET Mastery Quest to practise 15,000+ PYQ and 2027-syllabus questions.