Answer:
Option-B
Explanation:
In the given question, the condition of the person is mentioned which says that he felt breathless while walking and later while lying down.
The most probable reason for the condition in the give question is that this condition is the result of the failure of the left side of the heart as the left side of the heart that is right atrium receives the oxygenated blood from the lungs and then left ventricle pump the blood to the body.
Since the person is not able to breathe therefore the volume of the lungs is occupied by something in the given case is blood due to the failure of the left heart.
Thus, Option-B is the correct answer.
Carbon monoxide is the answer.
The answer would be 2 placenta. A thin walled sac that surrounds the fetus during pregnancy. The sac is filled with amniotic fluid(liquid made by fetus) and the amnion(the membrane that covers the fetal side of the placenta)