Which lifting agent is characterized by air rising due to heating from the Earth's surface?

The lifting agent characterized by air rising due to heating from the Earth's surface is known as convection. This process occurs when the sun heats the Earth's surface, causing the air at the surface to warm up. Warm air is less dense than cooler air, so as it heats up, it rises. As it rises, it may cool and contribute to cloud formation and weather patterns.

Mechanical turbulence refers to the chaotic property of air flows caused by obstacles on the surface, such as buildings or terrain, and does not specifically relate to the heating of air by the ground. Orographic lift involves air being forced to rise over mountains or hills, whereas frontal lift occurs when a warmer air mass is lifted over a cooler one due to a front. Neither of these processes is directly associated with the heating of the Earth's surface in the way convection is. Thus, convection is the correct choice as it effectively describes the process of rising air caused by thermal heating.