So for the answer for this one is going to be d
Answer:
A. <em>provide</em><em> </em><em>structure</em><em> </em><em>and </em><em>protection</em><em> </em>
<em>hope</em><em> it</em><em> helps</em>
I think it is because the cold air is more dense than the hot air so the less dense air which is the warm air rises
