Genotype of the plants remain the same throughout the breeding period in
I) Clonal selection
II) Pureline selection
III) Mass selection

Options

A. II only correct
B. I and III correct
C. II and III correct
D. I only correct

Answer

To solve the question regarding which breeding method maintains the same genotype of plants throughout the breeding period, we can analyze each option:

### Step-by-Step Solution:

1. **Understanding Genotype**:
- Genotype refers to the genetic constitution of an organism. In the context of plant breeding, it is crucial to determine which method keeps the genotype constant.

**Hint**: Remember that genotype is related to the genetic makeup of the plants.

2. **Analyzing Clonal Selection**:
- Clonal selection is a method of asexual reproduction where plants are propagated from a single parent plant. Since this method does not involve sexual reproduction, there is no genetic variation introduced. Therefore, the genotype remains the same throughout the breeding period.

**Hint**: Think about how asexual reproduction works and how it affects genetic variation.

3. **Analyzing Pure Line Selection**:
- Pure line selection involves selecting plants that are homozygous for certain traits. This method is based on sexual reproduction, which can introduce genetic variation due to the mixing of genes. Thus, the genotype can change over generations.

**Hint**: Consider how sexual reproduction can lead to new combinations of genes.

4. **Analyzing Mass Selection**:
- Mass selection is another breeding method that involves selecting a large number of plants based on their phenotypic traits. This method also relies on sexual reproduction and can lead to genetic variation, meaning the genotype may change.

**Hint**: Reflect on how selecting multiple plants can introduce variations in the offspring.

5. **Conclusion**:
- Based on the analysis, the only method where the genotype of the plants remains the same throughout the breeding period is **Clonal Selection**.

### Final Answer:
The correct answer is **I) Clonal Selection**.

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