The main casuse for the discovery of laws of heredity by Mendel.

Options

A. He analysed every trait independently
B. He was lucky that he did not come across linkage
C. His plants were true breeding
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Mendel's Work**: Gregor Mendel is known as the father of genetics for his pioneering work on the inheritance of traits in pea plants. He conducted experiments to understand how traits were passed from one generation to the next.

2. **Analyzing Traits Independently**: One of the main reasons for Mendel's success was his method of analyzing each trait independently. He focused on one trait at a time, such as flower color or seed shape, which allowed him to observe clear patterns of inheritance without the confusion of multiple traits interacting.

3. **True Breeding Plants**: Mendel used true-breeding plants, which are plants that consistently produce offspring with the same traits when self-fertilized. This ensured that the traits he was studying were stable and could be reliably tracked through generations.

4. **Avoiding Linkage**: Mendel was fortunate that the traits he studied were not linked, meaning they were located on different chromosomes and assorted independently during gamete formation. This independence allowed him to formulate his laws of inheritance without the complications that linkage would introduce.

5. **Conclusion**: Given these factors, the discovery of the laws of heredity by Mendel can be attributed to his methodical approach of analyzing traits independently, his use of true-breeding plants, and his luck in avoiding linkage. Therefore, the correct answer to the question is **option D: all of the above**.

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