M Mr. Dubey 🎓 Coach ⭐ 103.11K Points 📊 MySQL Q. What is a primary key? (A) A key that allows duplicate values (B) A key that can be null (C) A unique key used to identify rows (D) A key for foreign tables 👁️ Show Answer 💬 Discuss 🔗 Share ⚡Menu ✅ Correct Answer: (C) A unique key used to identify rows Explanation: A primary key uniquely identifies each record in a table and cannot be null.