How Does an Open Circulatory System Differ from a Closed

How does an open circulatory system differ from a closed one?

A) An open circulatory system has vessels that open into cavities called sinuses whereas a closed circulatory system has only vessels.
B) A closed circulatory system is completely encased in the body cavity whereas the open one is not.
C) An open circulatory system opens into the heart whereas the closed circulatory system does not.
D) An open circulatory system opens into arteries and is drained by veins whereas in a closed one it is just the reverse.
E) An open circulatory system drains into the mantle cavity whereas a closed circulatory system drains into the hemolymph.