Read the following text and answer the following questions on the basis of the same:
A typical anther is bilobed. It is a tetragonal structure consisting of four microsporangia. These microsporangia form pollen sac which on maturity gets filled with a pollen grains. Pollen grains represent the male gametophytes, their cell wall is very hard. Pollen grains of many species cause severe allergies which cause various diseases in human beings.
Select the odd one out with respect to wall layers of microsporangium in flowering plants.

Options

A. Integument
B. Tapetum
C. Endothecium
D. Middle layers

Explanation

To solve the question regarding the odd one out with respect to the wall layers of microsporangium in flowering plants, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Microsporangium**:
- A microsporangium is a part of the anther, which is the male reproductive structure in flowering plants (angiosperms). It contains pollen sacs where pollen grains develop.

2. **Identify the Wall Layers of Microsporangium**:
- The typical wall layers of a microsporangium include:
- **Epidermis**: The outermost layer.
- **Endothecium**: The second layer, which helps in the dehiscence of the anther.
- **Middle Layer**: The third layer, which provides support.
- **Tapetum**: The innermost layer, which nourishes the developing pollen grains.

3. **Review the Options**:
- The question asks to select the odd one out from the options provided. The options are likely to include:
- A) Integument
- B) Tapetum
- C) Endothecium
- D) Middle Layer

4. **Analyze Each Option**:
- **Option A: Integument**: This is a layer found in ovules, not in microsporangia. It forms the seed coat after fertilization.
- **Option B: Tapetum**: This is indeed a wall layer of the microsporangium.
- **Option C: Endothecium**: This is also a wall layer of the microsporangium.
- **Option D: Middle Layer**: This is another wall layer of the microsporangium.

5. **Identify the Odd One Out**:
- Since the integument is not a wall layer of microsporangium and is instead associated with ovules, the odd one out is **Option A: Integument**.

### Final Answer:
The odd one out with respect to wall layers of microsporangium in flowering plants is **Option A: Integument**.

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