Question

what do urban areas often replace vegetation with, contributing to heat islands?
more trees
lakes and ponds
concrete and steel
farmland

Explanation:

Urban areas often replace vegetation with concrete and steel. Concrete and steel have high heat - absorption and retention properties. Vegetation, on the other hand, has cooling effects like evapotranspiration. Replacing vegetation with concrete and steel reduces these cooling mechanisms and increases heat storage, contributing to the urban heat island effect.

Answer:

concrete and steel