(C) is the right answer.
Leucocytes are also known as white blood cells (WBC) as they are colourless due to the lack of haemoglobin. They are nucleated and are relatively lesser in number which averages 6000-8000 mmñ3 of blood. Leucocytes are generally short lived. We have two main categories of WBCs ñ granulocytes and agranulocytes. Neutrophils, eosinophils and basophils are different types of granulocytes, while lymphocytes and monocytes are the agranulocytes. Neutrophils and monocytes (6-8 per cent) are phagocytic cells which destroy foreign organisms entering the body.