oldest phloem is

Options

A. primary phloem
B. secondary phloem
C. crushed phloem
D. intermediate phloem.

Answer

To determine which type of phloem is the oldest, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Types of Phloem**:
- There are different types of phloem: primary phloem, secondary phloem, crushed phloem, and intermediate phloem.

2. **Identify the Oldest Phloem**:
- The term "oldest phloem" refers to the first formed phloem in the plant.

3. **Differentiate Between Primary and Secondary Phloem**:
- Primary phloem is formed during the initial stages of growth and is the first type of phloem to develop.
- Secondary phloem is formed later as the plant grows and adds new layers.

4. **Conclusion**:
- Since primary phloem is the first formed phloem, it is also considered the oldest phloem in the plant.
- Therefore, the correct answer is **primary phloem**.

### Final Answer:
The oldest phloem is **primary phloem**.

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