A : Poultry farming has definite advantage over live-stock rearing
R : Poultry birds are easy to raise, can be acclimatised to a wide range of climatic conditions, have short life span and are prolific breeders

Answer

### Step-by-Step Solution:

1. **Understanding the Assertion and Reason**:
- The assertion states that "Poultry farming has definite advantages over livestock rearing".
- The reason given is that "Poultry birds are easy to raise, can be acclimatized to a wide range of climatic conditions, have a short lifespan, and are prolific breeders".

2. **Defining Poultry Farming and Livestock Rearing**:
- Poultry farming involves raising domestic birds such as chickens, turkeys, geese, and ducks primarily for meat and eggs.
- Livestock rearing involves raising larger animals like sheep, pigs, goats, buffalo, and cows for milk and meat production.

3. **Comparing Space Requirements**:
- Poultry farming requires less space compared to livestock rearing, making it more feasible for small-scale operations.

4. **Cost-Effectiveness**:
- Poultry birds are generally less expensive to raise than larger livestock animals, contributing to lower operational costs.

5. **Lifespan and Returns**:
- Poultry birds have a shorter lifespan, which allows for quicker turnover and higher returns in a shorter time frame compared to livestock.

6. **Breeding Characteristics**:
- Poultry birds are prolific breeders, meaning they can produce a large number of offspring, enhancing profitability.

7. **Climatic Adaptability**:
- Poultry birds can adapt to a wide range of climatic conditions, making them more versatile for different farming environments.

8. **Conclusion**:
- Both the assertion and the reason are true. The reason supports the assertion, indicating that poultry farming does indeed have advantages over livestock rearing.

### Final Answer:
Both the assertion (A) and the reason (R) are true, and the reason (R) correctly explains the assertion (A).

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