Cornea transplantation is outstandingly successful because

Options

A. cornea is easy to preserve
B. cornea is not linked up with blood vascular and immune systems
C. the technique involved is very simple
D. cornea is easily available

Explanation

**Step-by-Step Solution:**

1. **Understanding Cornea Transplantation**: Cornea transplantation involves replacing a damaged or diseased cornea with a healthy one from a donor. The success of this procedure can depend on various factors.

2. **Evaluating the Options**:
- **Option 1**: "Cornea is easy to preserve." This statement is incorrect because while some organs can be preserved, the success of transplantation relies more on the body's acceptance of the graft rather than preservation alone.

- **Option 2**: "Cornea is avascular." This is the correct option. The cornea does not have a blood supply, which means that it is less likely to trigger an immune response that leads to rejection. The absence of blood vessels means that the immune cells (like T lymphocytes) that usually mediate rejection do not have access to the cornea.

- **Option 3**: "Technique involved is very simple." This statement is misleading. While the surgical technique may be straightforward, the complexities of the immune response and the need for precise matching of donor and recipient are significant factors in the success of the transplant.

- **Option 4**: "Cornea is easily available." This is also incorrect. While corneas can be donated, they are not as readily available as some other tissues.

3. **Conclusion**: Based on the analysis of the options, the most compelling reason for the outstanding success of cornea transplantation is that the cornea is avascular, which minimizes the risk of immune rejection.

**Final Answer**: Cornea transplantation is outstandingly successful because the cornea is avascular.

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