The correct option is B The blood cells contain haemoglobin
Earthworms have a closed circulatory system and hence their blood is confined to the heart and blood vessels. They have organs called blood glands present in the 4th, 5th and 6th segments. These glands produce blood cells as well as haemoglobin. The haemoglobin is dissolved in the plasma and not present in the blood cells as seen in humans. These cells are phagocytic in nature. That means they can engulf foreign particles such as pathogens.