Mendel was successful in formulating the laws of inheritance whereas his predecessors were not because

Options

A. He studied one clear-cut character at a time
B. The character studied by him were present on separate chromosomes
C. Of the right choice of material
D. He kept accurate records of his experiments.

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks why Mendel was successful in formulating the laws of inheritance while his predecessors were not. This requires us to analyze Mendel's methodology and compare it with that of earlier scientists.

2. **Mendel's Methodology**: Mendel conducted his experiments using pea plants (Pisum sativum) and focused on specific traits. He selected pure breeding varieties, which ensured that the traits were consistent and reliable.

3. **Study of One Character at a Time**: One of the key reasons for Mendel's success was his approach of studying one clear-cut character at a time (e.g., flower color, seed shape). This allowed him to isolate the effects of each trait and understand the inheritance patterns without the confusion of multiple traits interacting simultaneously.

4. **Predecessors' Approach**: In contrast, Mendel's predecessors often studied multiple traits at once. This made it difficult for them to discern the inheritance patterns because the interactions between different traits could obscure the results.

5. **Use of Statistical Methods**: Mendel applied statistical analysis and the laws of probability to interpret his results. This scientific approach helped him to formulate his laws of inheritance, such as the Law of Segregation and the Law of Independent Assortment.

6. **Conclusion**: Therefore, the primary reason Mendel was successful in formulating the laws of inheritance was that he studied one clear-cut character at a time, allowing for a more straightforward analysis of inheritance patterns.

### Final Answer:
Mendel was successful in formulating the laws of inheritance whereas his predecessors were not primarily because he studied one clear-cut character at a time.

---