Most abundant protein in animal world is:

Options

A. RuBisCo
B. Collagen
C. Glycogen
D. None of the above

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the most abundant protein in the animal kingdom. To answer this, we need to identify proteins that are prevalent in animals.

2. **Identifying Potential Candidates**:
- The transcript mentions several proteins, including Rubisco, collagen, and glycogen.
- Rubisco is primarily associated with plants and is involved in photosynthesis, so it is not the answer for the animal kingdom.
- Glycogen is a polysaccharide, not a protein, so it cannot be the answer either.

3. **Focusing on Collagen**:
- The transcript highlights collagen as a protein found in connective tissues, which are abundant in animals.
- Collagen provides structural support and is a major component of skin, bones, tendons, and ligaments.

4. **Conclusion**: Based on the information provided, the most abundant protein in the animal world is collagen.

### Final Answer:
The most abundant protein in the animal world is collagen.

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