The pathogen free plants are obtained from:

Options

A. Seeds
B. Shoot meristem culture
C. Root culture
D. Embryo cuture

Answer

### Step-by-Step Solution:

1. **Understanding Pathogen-Free Plants**:
- Pathogen-free plants are those that are free from any diseases or pathogens, such as viruses or bacteria. These plants are crucial for ensuring healthy crops and maintaining plant health.

2. **Introduction to Tissue Culture**:
- Tissue culture is a technique used to grow plants in a controlled environment, typically in a laboratory. This method allows for the mass production of plants from a small piece of plant tissue.

3. **Identifying Plant Parts for Tissue Culture**:
- Various parts of a plant can be used for tissue culture, including meristems, shoots, roots, leaves, and embryos. However, not all parts are equally effective in producing pathogen-free plants.

4. **Focusing on the Meristem**:
- The meristem is a region in plants where cells are actively dividing. This area is crucial because it is typically free from viruses and other pathogens.

5. **Process of Obtaining Pathogen-Free Plants**:
- To obtain pathogen-free plants, the meristem can be excised from a diseased plant and cultured in vitro (in a laboratory setting). Since the meristem cells are actively dividing, they do not support the growth of viruses, allowing for the regeneration of healthy plants.

6. **Conclusion**:
- Therefore, the correct answer to the question is that pathogen-free plants are obtained from **meristem culture**.

### Final Answer:
Pathogen-free plants are obtained from **meristem culture**.