The correct answer is enters into LA and exits via LV.Concept:Double Circulation:In human beings, the blood passes through the heart twice. Once through the left side and once through the right side. Explanation:Structure of the human heart:The heart is divided into right and left halves through a dividing wall called the septum. It has four chambers; two upper chambers called atria and two lower chambers called ventricles.So, the four chambers are the left atrium (LA), right atrium (RA), left ventricle (LV), and right ventricle (RV).Circulation of blood:The oxygenated blood coming from the lungs enters the LA and then exits through LV.The blood is then transferred to all the body parts through arteries and capillaries.The body consumes oxygen and produces carbon dioxide. The blood gets deoxygenated and carries it to the heart.The deoxygenated blood enters into RA and exits through RV. Then, it goes to the lungs where it is oxygenated.