D. by the unequal heating of earth's surface is for sure the correct answer.
As we know by ideal gas equations that
[tex]PV = nRT[/tex]
so here as the temperature of gas increases the density of air at that place will go down
Due to this density decrease in air the pressure also decreased
Now at some other place we will have less temperature so at that place density is high and hence pressure will be high
Now due to this temperature difference we will have density difference which will cause change in pressure
now this change in pressure will cause the wind blow from high pressure to low pressure region
so the correct answer will be
d. by the unequal heating of earth’s surface.
