Question

which of these is the most common result of greenhouse gases altering the atmosphere of earth?

an increase in the air temperature
a decrease in the air density
an increase in the intensity of visible light
a decrease in the thickness of the ozone layer

Explanation:

Greenhouse gases trap heat in the Earth's atmosphere. This trapped heat leads to an increase in the overall air temperature of the planet. A decrease in air density is not the main effect of greenhouse gases. Greenhouse gases do not increase the intensity of visible light. A decrease in the ozone layer thickness is mainly due to substances like chlorofluorocarbons (CFCs), not greenhouse gases.

Answer:

an increase in the air temperature