Stems are modified into flattened structures, which carryout photosynthesis in

Options

A. Euphorbia
B. Opuntia
C. Bougainvillea
D. Colocasia

Answer

To solve the question "Stems are modified into flattened structures, which carry out photosynthesis in," we will analyze the options provided and determine which plant has stems that fit this description.

### Step-by-Step Solution:

1. **Understand the Question**: The question is asking for a plant where the stems are modified into flattened structures that perform photosynthesis. This indicates that the stems have taken on a leaf-like function.

2. **Evaluate the Options**:
- **Option A: Group Phobia**: This refers to a group of plants where the stems are typically fleshy and cylindrical. Since the stems are not flattened, this option is incorrect.

- **Option B: Opuntia**: This is a genus of cacti known for its flattened stem segments called pads (or cladodes). These pads are capable of photosynthesis, which aligns perfectly with the question. Therefore, this option is a strong candidate for the correct answer.

- **Option C: Bougainvillea**: In Bougainvillea, the stems are modified to form thorns for protection, not for photosynthesis. Thus, this option is incorrect.

- **Option D: Colocasia**: This plant is known for its large leaves and tuberous roots, which store food. The stems do not serve the purpose of photosynthesis in a flattened structure. Hence, this option is also incorrect.

3. **Conclusion**: After evaluating all the options, the only plant that has stems modified into flattened structures that carry out photosynthesis is **Opuntia**.

### Final Answer:
The correct answer is **Opuntia**.

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