Most of our crop plants are

Options

A. autopolyuloid in origin
B. allopolyploid in origin
C. mixed genotypic in origin
D. ehterozyous in origin

Explanation

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of most crop plants. The options provided are:
- Autopolyploid in origin
- Allopolyploid in origin
- Mixed genotypic in origin
- Heterozygous in origin

2. **Defining Key Terms**:
- **Autopolyploidy**: This refers to a condition where there is an increase in the number of chromosome sets within a single species. For example, if a plant has a diploid set of chromosomes (2n), it can become tetraploid (4n) through autopolyploidy.
- **Allopolyploidy**: This occurs when two different species hybridize and then undergo chromosome doubling, resulting in a new species with combined chromosome sets.
- **Mixed Genotypic Origin**: This term generally refers to plants that have a combination of different genetic backgrounds but does not specifically relate to polyploidy.
- **Heterozygous Origin**: This refers to having different alleles at a gene locus, which is not directly related to the chromosome set number.

3. **Analyzing the Options**:
- Most crop plants are known to be derived from autopolyploidy, which leads to advantageous traits such as larger fruit size and thicker leaves due to the increased chromosome sets.

4. **Conclusion**: Based on the definitions and understanding of the terms, the correct answer to the question is that most of our crop plants are **autopolyploid in origin**.

**Final Answer**: Most of our crop plants are autopolyploid in origin.

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