The roof of the cranium of frog is formed by

Options

A. parasphenoid
B. alisphenoid
C. frontoparietal
D. orbitosphenoid

Explanation

To solve the question regarding the formation of the roof of the cranium of a frog, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Frog's Skull**:
- The frog's skull is divided into different regions, and we need to identify which parts contribute to the roof of the cranium.

2. **Identify the Relevant Regions**:
- The roof of the cranium specifically includes the frontal and parietal bones. The frontal bone is located at the front, while the parietal bone is located towards the back of the cranium.

3. **Analyze the Function of the Cranium**:
- The cranium serves as a protective casing for the brain, and the roof is formed by the frontal and parietal bones, which together create a flattened structure.

4. **Examine the Articulation**:
- The frontal and parietal bones are articulated together by sutures, which are fibrous joints that connect the bones of the skull.

5. **Select the Correct Answer**:
- Based on the information gathered, the roof of the cranium of a frog is formed by the fronto-parietal region. Therefore, the correct answer is option 3, which states "fronto-parietal."

### Final Answer:
The roof of the cranium of a frog is formed by the fronto-parietal region.

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