R Ram Sharma 🎓 Coach ⭐ 193.88K Points 📊 Biology Q. The main constituent of haemoglobin is (A) Iron (B) chlorine (C) calcium (D) None of the above 👁️ Show Answer 🔗 Share ⚡Menu ✅ Correct Answer: (A) Iron You must be Logged in to update hint/solution 💬 Discussion 💬 Comment