Polyploidy gives

Options

A. Hybrid vigour
B. Improved varieties
C. Gigas effect
D. All the above

Answer

### Step-by-Step Solution:

1. **Understanding Polyploidy**:
- Polyploidy refers to the condition in which an organism has more than two complete sets of chromosomes. In simpler terms, it means that instead of the usual diploid number (two sets), there are multiple sets (triploid, tetraploid, etc.).

2. **Example of Polyploidy**:
- For instance, humans typically have 46 chromosomes (23 pairs). If an individual has 47, 48, or more chromosomes, this condition is classified as polyploidy.

3. **Effects of Polyploidy**:
- Polyploidy can lead to various biological effects. One significant effect is known as the "Gigas effect" or "Gigas phenomenon," where polyploid organisms often exhibit increased size and vigor compared to their diploid counterparts.

4. **Analyzing the Options**:
- The question likely provides several options regarding what polyploidy gives rise to.
- The options include:
- A) Hybrid vigor
- B) Improved variation
- C) Gigas effect
- D) Another incorrect option

5. **Selecting the Correct Answer**:
- Hybrid vigor refers to the enhanced characteristics seen in hybrids, which is not directly related to polyploidy.
- Improved variation does not specifically describe the outcome of polyploidy.
- The Gigas effect is directly associated with polyploidy, making it the correct choice.
- Therefore, the correct answer is the "Gigas effect."

### Final Answer:
Polyploidy gives rise to the Gigas effect.

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