Haploids are more suitable for mutation studies than the diploids. This is because

Options

A. All mutations, whether dominant or recessive are expressed in haploid
B. Haploids are reproductively more stable than diploids
C. Mutagens penetrate in haploids more effetively than diploids
D. Haploids are more abundant in nature than diploids

Answer

To answer the question "Haploids are more suitable for mutation studies than the diploids. This is because," we can analyze the options provided and arrive at the correct reasoning step by step.

### Step-by-Step Solution:

1. **Understanding Haploids and Diploids**:
- Haploids (N) have only one set of chromosomes, while diploids (2N) have two sets of chromosomes. This fundamental difference is crucial in understanding how mutations are expressed.

2. **Expression of Mutations**:
- In haploids, there is only one allele for each gene. This means that any mutation that occurs, whether it is dominant or recessive, will be expressed directly because there is no second allele to mask it.

3. **Dominant and Recessive Mutations**:
- In diploids, a recessive mutation may not be expressed if a dominant allele is present. Therefore, studying mutations in diploids can sometimes lead to incomplete or misleading results regarding the presence of mutations.

4. **Conclusion**:
- Since all mutations (both dominant and recessive) are expressed in haploids, they are more suitable for mutation studies. This makes option one the correct answer: "All mutations whether dominant or recessive are expressed in haploid."

### Final Answer:
Haploids are more suitable for mutation studies than diploids because all mutations, whether dominant or recessive, are expressed in haploids.