Which of the following plants have stony endosperm?

Options

A. Castor and groundnut
B. Areca nut and phoenix dactyiifera
C. Wheat and coconut
D. Barley and date palm

Answer

To determine which of the following plants have stony endosperm, we need to understand what stony endosperm is and analyze the options provided.

### Step-by-Step Solution:

1. **Understand Stony Endosperm**:
- Stony endosperm refers to a hard type of endosperm found in certain seeds. It is characterized by the seed obtaining all its nutrients in one step during its life cycle, leading to a hard texture.

2. **Analyze the Options**:
- **Option A: Castor**:
- Castor seeds have a different type of endosperm formation, not stony. Therefore, this option is incorrect.
- **Option B: Erycinut (Betelnut) and Phoenix dactylifera (Date Palm)**:
- Both Erycinut and Phoenix dactylifera are known to have stony endosperm. This option is correct.
- **Option C: Wheat**:
- Wheat seeds have a different type of endosperm, not stony. Therefore, this option is incorrect.
- **Option D: Barley**:
- Barley has an albuminous type of endosperm, which is not stony. Therefore, this option is incorrect.

3. **Conclusion**:
- The only option that correctly identifies plants with stony endosperm is **Option B: Erycinut and Phoenix dactylifera**.

### Final Answer:
The plants that have stony endosperm are **Erycinut and Phoenix dactylifera**.

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