Answer:
The correct answers are options B and D which are decreases as altitude increases and results from a column of air pushing on an area respectively.
Step-by-step explanation:
The air pressure is inversely proportional to the altitude. Higher the altitude lower the air pressure.
Air pressure is the amount of force by air particles on a unit area.
As we move above the particles of air becomes lower. Hence the pressure decreases at high altitude.
Air pressure is also related with the column of air pushing on a unit area.