Common polysaccharide found in ground substance of connective tissue include :

Options

A. Hyaluronic acid
B. Melatonin
C. Cholesterol
D. All of the above

Answer

To answer the question about common polysaccharides found in the ground substance of connective tissue, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Ground Substance of Connective Tissue**:
- The ground substance is a component of the extracellular matrix in connective tissue. It consists of water, proteins, and various polysaccharides.

2. **Recognize Common Polysaccharides**:
- One of the main polysaccharides found in the ground substance is **hyaluronic acid**. It is a glycosaminoglycan that plays a crucial role in maintaining the structure and function of connective tissues.

3. **Evaluate the Options**:
- **Option 1: Hyaluronic Acid** - This is a correct answer as it is a common polysaccharide in the ground substance.
- **Option 2: Melatonin** - This is incorrect because melatonin is a hormone produced by the pineal gland, not a polysaccharide.
- **Option 3: Cholesterol** - This is also incorrect as cholesterol is a lipid found in cell membranes, not a polysaccharide.
- **Option 4: All of the Above** - This option is incorrect since only hyaluronic acid is a polysaccharide relevant to the question.

4. **Conclusion**:
- The only common polysaccharide found in the ground substance of connective tissue from the given options is **hyaluronic acid**.

### Final Answer:
The common polysaccharide found in the ground substance of connective tissue is **hyaluronic acid**.

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