How do hot air and cold air behave when they meet?

Answer: A. Hot air rises and cold air settles down

The correct answer is A. Hot air rises and cold air settles down.
When air is heated, it expands and becomes less dense, causing it to float upward. Cold air is denser and heavier because its molecules are packed closer together, so gravity pulls it downward. This interaction creates a natural circulation called a convection current. In nature, this process is the primary driver behind wind and various weather patterns.

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