Single shield shaped cotyledon of grass is known as:-

Options

A. Tigellum
B. Scutellum
C. Coleoptile
D. Coleorrhiza

Answer

To answer the question about the single shield-shaped cotyledon of grass, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Type of Seed**: Recognize that grass is a type of monocotyledonous plant. Monocots typically have one cotyledon.

2. **Understand Cotyledon Structure**: In monocots, the cotyledon often serves as a nutrient storage organ and can take various shapes.

3. **Specific Shape of Cotyledon**: The question specifies a "shield-shaped" cotyledon. This is a distinctive feature of certain monocot seeds.

4. **Recall the Terminology**: The terms provided in the question are:
- Tigellum
- Scutellum
- Cauliptyle
- Cauliriza

5. **Match the Description**: Among the options, the term "scutellum" specifically refers to the shield-shaped cotyledon found in monocots like grasses.

6. **Conclusion**: Therefore, the single shield-shaped cotyledon of grass is known as the **Scutellum**.

### Final Answer:
The single shield-shaped cotyledon of grass is known as **Scutellum**.

---