Answer:
option (d)
Step-by-step explanation:
The atmospheric pressure is given by
P = h x d x g
where, h is the height of air column from the top of the atmosphere, d be the density of air and g be the acceleration due to gravity.
As we go on heights, the density of air goes on decreasing, hence the atmospheric pressure decreases.
Thus, as we go up the molecules in the upper atmosphere are lighter.