Answer: Option C.
Gravity makes the blood flow backward
Explanation:
it difficult for your body to return blood from your feet when you sit for too long because gravity makes blood flow backward and this is because when you sit for long , it weakens the keg muscles because it is necessary for body movement so that blood will circulate or flow well. When the keg muscles becomes weak, it will slow blood flow in the leg and the force of gravity acting will make the blood flow backward and thus can cause a blood clot.
