What causes the temperatures in the lower troposphere to be warmer?

IN the troposhere the temperature generally decreases with altitude. The reason why the temperature decreases in altitude is that the troposhere's gases absorb very little of the incoming solar radiation. Instead, the ground absorbs this radiation and then heats the tropospheric air by conduction and convection. This causes the temperatures in the lower troposhere to be warmer.

Ibelieve it is c. a bird that nests only in a particular tree species.hope my answer has you : )