Kara uses a model that shows slight changes to earth’s motion through space over many thousands of years. this model her explain long-term climate change due to what variable?

a. volcanic activity
b. meteor or asteroid strikes
c. carbon dioxide levels in the atmosphere
d. input of solar energy

Option D, input of solar energy

Explanation:

It is clearly stated in the question that model of Kara shows the changes occurring in the motion of earth through ages. This means that as the direction of motion of earth changes the angle at which the solar rays strike the earth's surface also changes. Thus the net input of solar energy into the earths biome also changes. Sun is the major source of energy for planet earth and hence any change in solar energy input in earth will cause long term climatic changes. Also all climatic and essential geothermal, biological and nutrient cycle are governed by solar energy.

Hence, option D is correct.

a

explanation: