Consider the following statements.
I. Deer is a dioestrus animal.
II. Mouse is a monooestrus animal.
III. Dog Is a polyoestrus animal.
IV. Mammals are seasonal breeders.
Choose the correct codes.

Options

A. I, II and III
B. II, III and IV
C. I, II and IV
D. All are incorrect

Answer

To solve the question regarding the statements about the reproductive cycles of different animals, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement I: Deer is a dioestrus animal.**
- **Analysis:** Dioestrus animals exhibit two estrous cycles in a year. However, deer are classified as polyestrous animals, meaning they can have multiple estrous cycles throughout the year, particularly during their breeding season. Therefore, this statement is **incorrect**.

2. **Statement II: Mouse is a monoestrus animal.**
- **Analysis:** Monoestrus animals have only one estrous cycle per year. Mice, on the other hand, are polyestrous and can have multiple estrous cycles throughout the year without a specific breeding season. Thus, this statement is **incorrect**.

3. **Statement III: Dog is a polyestrus animal.**
- **Analysis:** Dogs are actually classified as monoestrous animals, meaning they typically have one estrous cycle per year. Therefore, this statement is **incorrect**.

4. **Statement IV: Mammals are seasonal breeders.**
- **Analysis:** While some mammals do breed seasonally, not all mammals are restricted to a specific breeding season. For example, humans and polyestrous animals like mice can reproduce at any time of the year. Hence, this statement is also **incorrect**.

### Conclusion:
All four statements are incorrect. Therefore, the correct answer is that none of the statements are true.

### Final Answer:
**All statements are incorrect.**

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