How does the ideal gas law relate to the Santa Ana winds? Decreasing altitude reduces the velocity of gas molecules. Increasing temperature leads to increased pressure in the air. Warm descending air expands, reducing its density, Air behaves like a solid during rapid movement.

The correct answer is:<br /><br />**Warm descending air expands, reducing its density.**<br /><br />### Explanation:<br />The Santa Ana winds are warm, dry winds that occur in Southern California and are caused by high-pressure systems over the inland deserts. These winds descend from higher altitudes to lower altitudes as they move toward the coast. The ideal gas law, expressed as **PV = nRT**, relates pressure (P), volume (V), number of moles of gas (n), the gas constant (R), and temperature (T). <br /><br />As the air descends, it is compressed due to increasing atmospheric pressure at lower altitudes. This compression causes the air to heat up (an adiabatic process). Warmer air is less dense than cooler air because the molecules spread out more as their kinetic energy increases. This reduced density contributes to the characteristic warm, dry nature of the Santa Ana winds.<br /><br />