The plant part which consists of two generations one within the other, is

Options

A. Germinated pollen grain
B. Embryo
C. Unfertilised ovule
D. Seed

Explanation

To solve the question "The plant part which consists of two generations, one within the other, is," we will analyze each option provided and determine which one contains both the gametophytic and sporophytic generations.

### Step-by-Step Solution:

1. **Understanding Generations**:
- In flowering plants, there are two generations:
- **Gametophytic Generation**: This is the haploid (n) phase that produces gametes (sperm and egg).
- **Sporophytic Generation**: This is the diploid (2n) phase that produces spores.

2. **Analyzing the Options**:
- **Option A: Germinated Pollen Grain**:
- A pollen grain consists of a vegetative cell and a generative cell, both of which are haploid. Therefore, it represents only the gametophytic generation.
- **Conclusion**: This option does not contain both generations.

- **Option B: Embryo**:
- An embryo is formed after fertilization when the male gamete fuses with the egg cell, resulting in a diploid zygote that develops into an embryo.
- **Conclusion**: The embryo represents only the sporophytic generation.

- **Option C: Unfertilized Ovule**:
- An unfertilized ovule contains the embryo sac, which is haploid (gametophytic generation) and also has diploid parts (the integuments and other structures).
- **Conclusion**: The unfertilized ovule contains both the gametophytic generation (in the embryo sac) and the sporophytic generation (in the other parts).

- **Option D: Seed**:
- A seed contains an embryo (diploid) and a seed coat (also diploid). It does not contain any haploid structures.
- **Conclusion**: The seed represents only the sporophytic generation.

3. **Final Conclusion**:
- The only option that contains both generations (gametophytic and sporophytic) is **Option C: Unfertilized Ovule**.

### Answer:
The plant part which consists of two generations, one within the other, is **unfertilized ovule**.

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