Endosperm is hard/stony in

Options

A. Areca nut
B. Date palm
C. lvory palm
D. all of these

Answer

### Step-by-Step Solution:

1. **Understanding Endosperm**:
- The endosperm is a tissue that provides nourishment to the developing embryo in seeds. It is formed from the fusion of a male gamete with the central cell of the ovule, which contains two polar nuclei, resulting in a triploid structure.

2. **Types of Endosperm Formation**:
- There are three main types of endosperm formation:
- **Nuclear Type**: In this type, karyokinesis (nuclear division) occurs without cytokinesis (cytoplasmic division), leading to a multinucleate cell. This type is common in coconuts.
- **Cellular Type**: Here, both karyokinesis and cytokinesis occur, resulting in a cellular structure. This type is seen in plants like petunia.
- **Helobial Type**: This is a combination of the two previous types, where the first division is followed by cytokinesis, and subsequent divisions are free nuclear.

3. **Identifying Hard/Stony Endosperm**:
- The question asks for examples of plants with hard or stony endosperm.
- The options provided include:
- Arecanut (Areca catechu)
- Date Palm (Phoenix dactylifera)
- Ivory Palm (Hyophorbe indica)
- All these plants are known to have hard or stony endosperm.

4. **Conclusion**:
- Therefore, the correct answer to the question is that endosperm is hard/stony in all of the mentioned plants: Arecanut, Date Palm, and Ivory Palm.