The correct answer is option 1: Both A and R are individually true and R is the correct explanation of A.
Explanation:
In subtropical and temperate areas, the amount of dust particles is indeed less compared to equatorial areas. This is supported by scientific research and studies which have shown that equatorial regions tend to have more dust due to the combination of factors such as higher temperatures, humidity, and lack of strong winds. These conditions in the equatorial areas facilitate the suspension and transport of dust particles in the atmosphere.
The reason provided, that the atmosphere is dry and windy in the subtropical and temperate areas, is a correct explanation for the lower amount of dust particles. Dry and windy conditions make it difficult for dust particles to remain suspended in the air for long. The strong winds in these areas also help disperse the dust particles, preventing their accumulation.
Therefore, both the assertion (A) and the reason (R) given are individually true, and the reason does provide an explanation for why the amount of dust particles is less in subtropical and temperate areas compared to equatorial areas.