Which of the following types of roots are correctly matched with their examples ?
I. Apogeotropic roots : Rhizophora
II. Absence of calyptra : Lemna
III. Velamen containing roots : vanda
IV. Moniliform roots : portulaca

Options

A. I and II
B. III and IV
C. I , II and IV
D. I , II , III and IV

Answer

To solve the question regarding the correct matching of types of roots with their examples, we will analyze each option step by step.

### Step 1: Analyze the first option
**I. Apogeotropic roots: Rhizophora**
- **Definition**: Apogeotropic roots are roots that grow against the force of gravity, typically found above the soil surface.
- **Example**: Rhizophora, a mangrove plant, has roots that emerge above the water and are adapted to its environment.
- **Conclusion**: This match is **correct**.

### Step 2: Analyze the second option
**II. Absence of calyptra: Lemna**
- **Definition**: Calyptra is a protective cap at the tip of the root, usually present in many plants.
- **Example**: Lemna, a type of duckweed, does not have a calyptra as it has a very simple root structure.
- **Conclusion**: This match is **correct**.

### Step 3: Analyze the third option
**III. Velamen containing roots: Vanda**
- **Definition**: Velamen is a spongy layer of tissue that covers the roots of some epiphytic plants, helping them absorb moisture from the air.
- **Example**: Vanda is an epiphytic orchid that has velamen-covered roots.
- **Conclusion**: This match is **correct**.

### Step 4: Analyze the fourth option
**IV. Moniliform roots: Portulaca**
- **Definition**: Moniliform roots are thickened, bead-like roots that store food.
- **Example**: Portulaca, also known as purslane, has fleshy, swollen roots that can be considered moniliform.
- **Conclusion**: This match is **correct**.

### Final Conclusion
All four options are correctly matched with their examples. Therefore, the correct answer is that all options (I, II, III, and IV) are correct.