Euploidy is

Options

A. One chromosome more than haploid set
B. One chromosome more than diploid set
C. One chromosome less than haploid set
D. Exact multiple of haploid set of chromosomes

Answer

**Step-by-Step Solution:**

1. **Understanding Euploidy**:
- Euploidy refers to a condition where an organism has one or more complete sets of chromosomes. This means that the number of chromosomes is an exact multiple of the haploid number (n).

2. **Analyzing the Options**:
- The question provides four options regarding what euploidy is:
- A) One chromosome more than haploid set
- B) One chromosome more than diploid set
- C) One chromosome less than haploid set
- D) Exact multiple of haploid set of chromosomes

3. **Evaluating Each Option**:
- **Option A**: "One chromosome more than haploid set" - This is incorrect as euploidy involves complete sets, not just a single chromosome.
- **Option B**: "One chromosome more than diploid set" - This is also incorrect for the same reason as above.
- **Option C**: "One chromosome less than haploid set" - This is incorrect as it suggests a reduction rather than a complete set.
- **Option D**: "Exact multiple of haploid set of chromosomes" - This is correct. Euploidy is characterized by having a complete set or multiple sets of chromosomes (e.g., diploid, triploid).

4. **Conclusion**:
- The correct answer to the question "Euploidy is" is **Option D: Exact multiple of haploid set of chromosomes**.

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