Questions: have a closed circulatory system. Flies Fish Shrimp

The answer is the second one: Fish have a closed circulatory system.

Explanation for each option:

1. Flies: Incorrect. Flies, like other insects, have an open circulatory system. In this system, the blood (hemolymph) is not confined entirely to vessels and instead bathes the organs directly in the body cavity.

2. Fish: Correct. Fish have a closed circulatory system, where the blood circulates within a network of blood vessels. This system allows for more efficient transport of nutrients and oxygen throughout the body.

3. Shrimp: Incorrect. Shrimp, like other crustaceans, have an open circulatory system. Their blood is not contained entirely within vessels and instead flows freely through cavities in the body.

In summary, fish are the only option among the three that possess a closed circulatory system.