The correct option is A platelet count in the blood
There are 3 types of cells in the body - red blood cells, white blood cells and platelets. Platelets help in the clotting of blood when there is a cut in the body. Low platelet count will lead to excessive bleeding. The red blood cells transport oxygen to all the cells in the body. The haemoglobin in the red blood cells gives red colour to the blood. The white blood cells help in defending the body against the germs that enter our body.