Which statement is true regarding high- or low-pressure systems?

A low-pressure area or trough is indeed characterized by rising air, which is a fundamental aspect of meteorology. In a low-pressure system, the atmospheric pressure decreases, leading to air being drawn in from surrounding areas. This incoming air converges at the surface and is forced to rise, which often results in cloud formation and precipitation. As the air rises, it cools and can lead to the development of various weather phenomena, including storms.

In contrast, a high-pressure system is typically associated with descending air, which creates stable atmospheric conditions and often leads to clear skies. Therefore, it is important to recognize the distinction between low-pressure systems, which are prone to active weather due to rising air, and high-pressure systems, which promote calm conditions due to descending air.