Snails and slugs have open circulatory system.

Answer

**Step-by-Step Text Solution:**

1. **Identify the Organisms**: Snails and slugs belong to the phylum Mollusca. This is the first step in understanding their biological classification.

2. **Understand the Circulatory System**: The circulatory system of snails and slugs is classified as an open circulatory system. This means that their blood (or hemolymph) is not contained entirely within blood vessels.

3. **Characteristics of Open Circulatory System**: In an open circulatory system, the blood (hemolymph) bathes the organs directly. This is different from a closed circulatory system where blood is confined to vessels.

4. **Circulation Dynamics**: The circulation in snails and slugs is relatively low-pressure, which allows the hemolymph to flow freely around the organs, providing them with nutrients and oxygen directly.

5. **Presence of Hemolymph**: Instead of hemoglobin, which is commonly found in the blood of many animals, snails and slugs have hemolymph. Hemolymph is a colorless or white fluid that serves a similar function to blood in other organisms.

6. **Conclusion**: Given these characteristics, the statement that "snails and slugs have an open circulatory system" is true. Their organs are directly bathed in hemolymph, confirming the nature of their circulatory system.

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