Which is most often a result of a warm air mass moving over a cooler air mass

When a warm air mass moves into an area of cooler air, the boundary between the air masses is called a warm front. The warmer, less-dense air slides up over the cooler, denser air in a wide, gentle slope. As the warm air cools, its relative humidity increases, and the water vapor condenses into clouds.

Explanation:

1."lessen the worth of ."

2."increase the worth of."

3." beyond the worth of."

4."against the worth of ."