The new varieties of plants are produced by

Options

A. selection and hybridisation
B. selection and introduction
C. mutation and selection
D. introduction and mutation

Explanation

To answer the question "The new varieties of plants are produced by?", we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Process of Plant Variety Development**:
- New varieties of plants are developed through specific techniques that enhance desirable traits such as yield, disease resistance, and adaptability.

2. **Identifying Key Techniques**:
- The two primary techniques involved in producing new plant varieties are **selection** and **hybridization**.
- **Selection** involves choosing parent plants that exhibit superior traits. This is a non-random process where plants with desirable characteristics are selected for breeding.
- **Hybridization** is the process of crossing selected parent plants to produce offspring (progeny) that inherit the desirable traits from both parents.

3. **Evaluating the Options**:
- **Option 1: Selection and Hybridization** - This option correctly identifies the two main techniques used in producing new plant varieties.
- **Option 2: Selection and Introduction** - While selection is important, introduction refers to bringing in new varieties from other regions, which is not the primary method for creating new varieties.
- **Option 3: Mutation and Selection** - Mutation can create variability, but it is not the main method for producing new varieties.
- **Option 4: Introduction and Mutation** - Similar to option 2, this does not focus on the key methods of creating new varieties.

4. **Conclusion**:
- Based on the understanding of the processes involved, the correct answer is **Option 1: Selection and Hybridization**.

### Final Answer:
The new varieties of plants are produced by **Selection and Hybridization**.

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