Which of the following is true ?

Options

A. umbel is a racemose inflorescene where all stalked flower aggregate on the flat receptacle
B. raceme is a racemose inflorescence having main axis shortened & flower born acropetally
C. spadix is a racemose inflorescence having pendulous spike with main axis much flattened
D. spike is a racemose inflorescence having sessile flowers

Explanation

To solve the question "Which of the following is true?", we will analyze each of the provided statements one by one and determine their validity.

### Step-by-Step Solution:

1. **Evaluate the First Statement:**
- **Statement:** "Umbel is an SNO with fluorescence where all stalked flowers abrogate on a flat receptacle."
- **Analysis:** This statement is incorrect. An umbel is a type of inflorescence where multiple flower stalks (pedicels) arise from a common point, resembling an umbrella. The description of "abrogate on a flat receptacle" is misleading.
- **Conclusion:** This statement is false.

2. **Evaluate the Second Statement:**
- **Statement:** "Resinase is a resinous inflorescence with a mean axis sorghum and flower born appropriately."
- **Analysis:** This statement is also incorrect. The term "resinase" is not commonly used in botany to describe an inflorescence. Instead, resin refers to a substance produced by certain plants. The description does not accurately represent any known inflorescence type.
- **Conclusion:** This statement is false.

3. **Evaluate the Third Statement:**
- **Statement:** "Aesthetics is a vast and large inflorescence having pendulous spike with mean excess moisture."
- **Analysis:** This statement is incorrect. The term "Aesthetics" does not refer to a botanical term for inflorescence. The description does not match any known inflorescence type.
- **Conclusion:** This statement is false.

4. **Evaluate the Fourth Statement:**
- **Statement:** "Spike is a resemblance to inflorescence."
- **Analysis:** This statement is true. A spike is a type of inflorescence where flowers are borne directly on an elongated axis without pedicels. The flowers are arranged acropetally (from the base to the tip).
- **Conclusion:** This statement is true.

### Final Answer:
The correct option for the question is **Option 4: Spike is a resemblance to inflorescence.**

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