Detailed Explanation:

✅ Option 1 – Correct: Kinetic energy to heat energy conversion involves frictional force. When objects move against each other (e.g., rubbing hands, braking vehicles), friction opposes motion and converts kinetic energy into heat energy.

❌ Option 2 – Incorrect: Potential energy to sound energy conversion (e.g., ringing bell, falling object hitting ground) does not require friction; it involves vibrations and mechanical energy transfer.

❌ Option 3 – Incorrect: Chemical energy to heat energy conversion (e.g., combustion, digestion) occurs through chemical reactions, not through frictional force.