A root is adventitous when it is

Options

A. Swollen
B. Growing in marshy places
C. Formed from parts other than radicle
D. Modified for storage.

Answer

To determine when a root is considered adventitious, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Root Development**:
- Roots typically develop from the radical part of the embryo. The radical elongates to form the primary root, which may branch into secondary and tertiary roots.

2. **Define Adventitious Roots**:
- Adventitious roots are those that do not develop from the radical. Instead, they arise from other parts of the plant, such as stems or leaves.

3. **Identify Characteristics of Adventitious Roots**:
- These roots can provide additional support or serve various functions, such as storage or adaptation to specific environments.

4. **Examples of Adventitious Roots**:
- Common examples include prop roots (e.g., in banyan trees) and stilt roots (e.g., in sugarcane and maize). These roots arise from the stem rather than the radical.

5. **Analyze the Options**:
- Based on the definitions and examples discussed, we can evaluate the provided options to find the correct answer regarding when a root is considered adventitious.

6. **Select the Correct Answer**:
- The correct answer is that a root is adventitious when it develops from parts of the plant other than the radical.

### Final Answer:
A root is adventitious when it develops from parts of the plant other than the radical.

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