Answer:
Blood cells picking up and carrying oxygen from the lungs to the body's cells (Ans. A)
Explanation:
Red blood cells (RBC) have the main function of carrying oxygen. These cells are present in our blood & their journey begins in the lungs where they picking up & carrying oxygen from the air we breathe. Then the blood cells travel to the heart through the veins, which pump out the blood & delivering oxygen to all parts of our body.
So, the correct option is A.