Identify the correct combination

Options

A. Neem - Absence of buds in the axile of leaflets-Pinnately compound leaf
B. Sunflower - Flowers brought to same height due to varied lengths of pedicels - Involucre of bracts
C. Carrot - Flowers brought to same height due to varied lengths of pedicels - Involucre of bracts
D. Pistia - Discoid stem - Lateral branch with many internodes.

Answer

To solve the question "Identify the correct combination," we need to analyze each of the provided options based on the characteristics of the plants mentioned. Here’s a step-by-step breakdown:

### Step 1: Analyze the First Option - Neem
- **Claim**: Neem has an absence of buds in the axil of leaflets and pinnately compound leaves.
- **Fact Check**: Neem actually has compound leaves and buds are present in the axil of leaflets.
- **Conclusion**: This option is incorrect.

### Step 2: Analyze the Second Option - Sunflower
- **Claim**: Sunflower has flowers brought to the same height due to varied lengths of pedicels and an involucre of bracts.
- **Fact Check**: Sunflower does have an alternate phyllotaxy and an inferior ovary, but the arrangement of flowers at the same height due to varied lengths of pedicels is characteristic of a corymb, which is not typical for sunflowers.
- **Conclusion**: This option is incorrect.

### Step 3: Analyze the Third Option - Carrot
- **Claim**: Carrot has flowers brought to the same height due to varied lengths of pedicels and an involucre of bracts.
- **Fact Check**: The description of flowers brought to the same height due to varied lengths of pedicels is more accurate for coriander, while carrot flowers arise from a single point (umbel inflorescence).
- **Conclusion**: This option is incorrect.

### Step 4: Analyze the Fourth Option - Pistia
- **Claim**: Pistia has a discoid stem and lateral branches with many internodes.
- **Fact Check**: Pistia is indeed an aquatic plant with a discoid stem and lateral branches that have short internodes, along with rosettes of leaves and tufted roots.
- **Conclusion**: This option is correct.

### Final Answer
Based on the analysis, the correct combination is **Option 4: Pistia**.

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