Q. Assertion Open circulatory system is found in most arthropods.
Reason Arthropods contain haemolymph which directly bathes internal tissues and organs.

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Solution:

Most arthropods certain molluscs and tunicates contain open circulatory system. In them, a fluid composed of blood mixed with tissue fluid bathes with internal tissues and organs directly. It oozes through spaces or cavities that surround the organs, this mixture of fluid is usually referred to as haemolymph.