Explanation:

- Option 1 (drops): This isn't correct. As temperature rises, air molecules move faster, facilitating quicker sound transmission.

- Option 2 (rises): The speed of sound increases with rising temperature because sound waves travel faster in warmer air where particles have more energy.

- Option 3 (remains constant): Sound speed isn't constant with temperature changes. It varies based on air particle energy.

- Option 4 (becomes unpredictable): Temperature changes predictably affect sound speeds, given consistent atmospheric conditions.