Vitamin B12 is a coordination complex of .........
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Co
Many molecules of living systems are coordination compounds, each with its own central metal ion. Vitamin B12, cyanocobalamin (the anti-pernicious anaemia factor), has cobalt at its centre.
So vitamin B12 is a coordination compound of cobalt.
NCERT (2026-27 edition):
Coordination Compounds
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| 19-05 S2 | 21-05 S2 | – | – | – |