Select the incorrect pair out of the following

Options

A. Monadelphous - Hibiscus
B. Diadelphous - Cucurbita
C. Polyadelphous -Citrus
D. Syngenesious - Helianthus

Explanation

To solve the question of selecting the incorrect pair from the given options, we can follow these steps:

### Step 1: Understand the Terms
First, we need to understand the terms used in the question:
- **Monodelphous**: Refers to a condition where all stamens are fused into a single group.
- **Diadelphous**: Refers to a condition where stamens are divided into two groups, typically characterized by a 9+1 arrangement or 5+5 arrangement.
- **Polydelphous**: Refers to a condition where stamens are divided into multiple groups.
- **Syngenesious**: Refers to a condition where anthers are fused together.

### Step 2: Analyze Each Pair
Next, we analyze each of the pairs provided:
1. **Monodelphous - Hibiscus**: This is correct as Hibiscus has all its stamens fused into one group.
2. **Diadelphous - Cucurbita**: This is incorrect. Cucurbita exhibits a synandrous condition, not diadelphous.
3. **Polydelphous - Citrus**: This is correct as Citrus has stamens that can be grouped into multiple clusters.
4. **Syngenesious - Helianthus**: This is correct as Helianthus (sunflower) has anthers that are fused.

### Step 3: Identify the Incorrect Pair
From our analysis, we see that the incorrect pair is:
- **Diadelphous - Cucurbita**: This is the incorrect pairing as Cucurbita does not exhibit diadelphous condition.

### Conclusion
Thus, the answer to the question is that the incorrect pair is **Diadelphous - Cucurbita**.

---