Which of the following is true?

Options

A. Frog has monocular vision
B. Frog has membrane present at the body surface
C. Frog is myopic (short sighted) on land
D. All of these are true

Explanation

To determine which of the statements about frogs is true, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1: Frog has monocular vision.**
- Monocular vision means that each eye can be used independently. Frogs have eyes positioned on the sides of their heads, allowing them to see in different directions simultaneously. This statement is true.

2. **Statement 2: Frog has a membrane present at the body surface.**
- Frogs possess a nictitating membrane, which is a protective layer that covers their eyes. This membrane helps protect their eyes while they are submerged in water and allows them to see underwater. This statement is also true.

3. **Statement 3: Frog is myopic (short-sighted) on land.**
- Myopia refers to the inability to see distant objects clearly. Frogs are indeed myopic on land, meaning they have difficulty focusing on distant objects when they are out of water. This statement is true as well.

4. **Statement 4: All of these are true.**
- Since all the previous statements (1, 2, and 3) have been confirmed to be true, this statement is also true.

### Conclusion:
The correct answer is that all of the statements about frogs are true. Therefore, the correct option is **"All of these are true."**

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