Most of the existing crops are products of

Options

A. Mass selection
B. Introduction
C. Hybridization
D. Pure line selection

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of most existing crops. We need to identify the process through which these crops were developed.

2. **Analyzing the Options**: The options provided are:
- A) Mass selection
- B) Introduction
- C) Hybridization
- D) Pure line selection

3. **Defining Each Option**:
- **Mass Selection**: This is a breeding method where a large number of plants are selected based on desirable traits, and these plants are used to produce the next generation. It allows for the accumulation of favorable traits over time.
- **Introduction**: This refers to the process of bringing new varieties of crops into a region or area. It does not necessarily pertain to the existing crops.
- **Hybridization**: This involves crossing two different varieties or species to produce hybrids, which may have improved traits. This is a method of crop improvement but not the primary source of most existing crops.
- **Pure Line Selection**: This method involves selecting plants that are genetically uniform. There is little to no genetic variation, which can limit adaptability.

4. **Identifying the Correct Answer**: Among the options, mass selection is the most relevant process that has contributed to the development of most existing crops. It allows for the selection of plants with desirable traits over generations, leading to the crops we have today.

5. **Conclusion**: Based on the analysis, the correct answer is **A) Mass selection**.

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