Stipules are modified into tendrils in :

Options

A. Gloriosa
B. Smilax
C. Lathyrus aphaca
D. Pisum sativum

Explanation

To solve the question regarding which plant has stipules modified into tendrils, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Stipules**: Stipules are small, leaf-like structures that are found at the base of the leaf stalk (petiole). Their primary function is to protect the developing leaf or bud.

2. **Identify the Function of Modified Stipules**: Stipules can be modified into various forms, one of which is tendrils. Tendrils are specialized structures that help climbing plants attach to supports, allowing them to grow upwards.

3. **Analyze the Given Options**: The options provided are:
- Gloriosa
- Smilax
- Lathyrus afaca
- Pisum sativum

4. **Determine the Climbing Nature of the Plants**: Among the options, we need to identify which plant is a climber:
- **Gloriosa**: A climbing plant known for its tendril-like structures.
- **Smilax**: A climbing monocotyledon that has modified stipules as tendrils.
- **Lathyrus afaca**: Also a climbing plant, but not specifically known for stipules as tendrils.
- **Pisum sativum**: Commonly known as pea, which has tendrils but they are not derived from stipules.

5. **Select the Correct Answer**: Based on the analysis, **Smilax** is the plant where stipules are modified into tendrils. Therefore, the correct answer is **Smilax**.

### Final Answer:
Stipules are modified into tendrils in **Smilax**.