The correct option is A Blood circulation happens in closed vessels in arthropods
Based on complexity and evolution, there are two types of circulatory systems- open type and closed type.
The open type circulatory system is observed in arthropods and non-cephalopod molluscs. In this type of circulatory system, the haemolymph fills the coelomic channels and such a coelom is called haemocoel. The body tissues come in direct contact with the circulating fluid. So the blood circulation does not happen in closed vessels in arthropods.
In the closed type circulatory system, the blood circulates in closed vessels. So the tissues are not in direct contact with blood. It is observed in annelids, cephalopod molluscs and chordates.
Fishes have a venous heart which receives only deoxygenated blood from the body parts and pumps it to the gills for oxygenation through the gaseous exchange. From the gills, the oxygenated blood is supplied to the body parts. So the heart pumps only deoxygenated blood in fishes.
The circulatory system distributes nutrients from the digestive system, oxygen from the respiratory organs, hormones from the endocrine glands etc to all the cells of the body.
It also transports carbon dioxide from body cells to the respiratory system, excretory substances like urea, ammonia etc. to the excretory organs.