Cornea is covered externally by a thin transparent membrane which is called

Options

A. sclerotic
B. conjunctiva
C. choroid
D. None of these

Explanation

**Step-by-Step Solution:**

1. **Identify the Structure**: The question asks about the external covering of the cornea. The cornea is the transparent front part of the eye that covers the iris, pupil, and anterior chamber.

2. **Recall the Membrane**: The thin transparent membrane that covers the cornea is known as the conjunctiva.

3. **Understand the Function**: The conjunctiva serves two primary functions:
- It provides protection to the cornea and the eye.
- It helps keep the eyeball moist by secreting mucus and tears.

4. **Conclude the Answer**: Based on the information gathered, the answer to the question is that the cornea is covered externally by the conjunctiva.

5. **Select the Correct Option**: If options are provided, select the one that states "conjunctiva" as the answer.

**Final Answer**: The cornea is covered externally by a thin transparent membrane called the conjunctiva.

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