Artificial insemination is advantageous because

Options

A. It is economical and success rate of fertilization is high
B. Several cows can be fertilized by the semen collected from one bull
C. The semen can be stored frozen for a long period and can be easily transported to remote parts of the country
D. All of these

Explanation

### Step-by-Step Solution:

1. **Define Artificial Insemination**:
- Artificial insemination (AI) is a reproductive technology that involves collecting semen from a male (bull, in the case of cattle) and introducing it into the female reproductive tract (cervix, vagina, or uterus) using specialized equipment.

2. **Identify Advantages of Artificial Insemination**:
- **Economical**: AI allows one bull to fertilize multiple cows, making it cost-effective.
- **High Success Rate**: The success rate of fertilization through AI is generally higher compared to natural mating.
- **Storage and Transportation**: Semen can be stored frozen for long periods, allowing for easy transportation to remote areas.
- **No Size Difference Concern**: AI eliminates the need to worry about size differences between male and female animals, as the procedure uses equipment to ensure proper placement.
- **Disease-Free Semen**: The semen collected can be tested for diseases, ensuring that it is disease-free before use.

3. **Conclusion**:
- Given the multiple advantages listed, the most comprehensive answer to the question of why artificial insemination is advantageous is that it encompasses all these benefits. Therefore, the correct answer is "all of these".

### Final Answer:
Artificial insemination is advantageous because it is economical, has a high success rate of fertilization, allows for the storage and transportation of semen, eliminates concerns about size differences, and ensures disease-free semen. Thus, the correct option is "all of these".

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