Select correct statements from the following:
a. In the majority of the dicotyledonous plants, the direct elongation
of the radicle leads to the formation of the primary root.
b. In monocotyledonous plants, the primary root is short-lived and is replaced by a large number of roots. These roots originate from the lowermost node of the stem and constitute the fibrous root system.
c. Adventitious roots are found in Monstera and banyan tree.
d. The fibrous root system is found in wheat and mustard plants.

Options

A. a and c only
B. a, b and c only
C. a, c and d only
D. All of the above

Answer

To solve the question, we need to evaluate each of the four statements regarding root systems in plants and determine which ones are correct.

### Step-by-Step Solution:

1. **Evaluate Statement A**:
- **Statement**: "In the majority of the dicotyledonous plants, the direct elongation of the radicle leads to the formation of the primary root."
- **Analysis**: This statement is correct. In dicots, the radicle (the embryonic root) elongates and develops into the primary root after germination.

2. **Evaluate Statement B**:
- **Statement**: "In monocotyledonous plants, the primary root is short-lived and is replaced by a large number of roots. These roots originate from the lowermost node of the stem and constitute the fibrous root system."
- **Analysis**: This statement is also correct. In monocots, the primary root does not persist for long and is replaced by a fibrous root system that arises from the nodes of the stem.

3. **Evaluate Statement C**:
- **Statement**: "Adventitious roots are found in Monstera and banyan tree."
- **Analysis**: This statement is correct. Both Monstera and banyan trees have adventitious roots that serve various functions, including support and nutrient absorption.

4. **Evaluate Statement D**:
- **Statement**: "The fibrous root system is found in wheat and mustard plants."
- **Analysis**: This statement is incorrect. While wheat (a monocot) has a fibrous root system, mustard (a dicot) has a tap root system.

### Conclusion:
The correct statements are A, B, and C.

### Final Answer:
- Correct Statements: A, B, C

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