Question

Following is (are) true about heart

(A)Oxygen-rich blood from the lungs comes to the left atrium

(B)De-oxygenated blood comes from the body to the upper chamber on the right,the right atrium, as it relaxes.the right atrium, as it relaxes.

(C)Valves ensure that blood does not flow backwards when the atria or ventricles contract

(D)All of the above​

Answer 1

Answer:

I think the option a

please follow mw

Answer 2

Answer:

Option a is your answer.

Explanation:

hope it helps