Microscopic structure having polar nuclei is

Options

A. (a) Pollen tube
B. (b) Embryo sac
C. (c) Pollen grain
D. (d) Male gamete

Answer

To answer the question "Microscopic structure having polar nuclei is", we will follow these steps:

### Step 1: Understand the Question
The question is asking for a specific microscopic structure that contains polar nuclei.

### Step 2: Identify Relevant Structures
In flowering plants, the structures involved in reproduction include several components such as the stigma, pollen tube, and embryo sac.

### Step 3: Define the Structures
- **Stigma**: This is the part of the flower that receives pollen grains. It does not contain polar nuclei.
- **Pollen Tube**: This structure is formed after pollen grains germinate and serves to transport male gametes to the ovule. It does not contain polar nuclei.
- **Embryo Sac**: This is the female gametophyte within the ovule of flowering plants. It contains several nuclei, including the polar nuclei.

### Step 4: Identify the Correct Answer
Among the options provided:
- A) Pollen Tube - Incorrect, as it does not contain polar nuclei.
- B) Embryo Sac - Correct, as it contains polar nuclei.
- C) Male Gamete - Incorrect, as it refers to the male reproductive cell and does not contain polar nuclei.

Thus, the correct answer is **B) Embryo Sac**.

### Final Answer
The microscopic structure having polar nuclei is the **Embryo Sac**.

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