All the following statements are correct, except

Options

A. Hyaline cartilage lacks fibers and is present in ster- num, hyoid, and ribs.
B. White fibrous cartilage is the strongest and is present in intervertebral discs.
C. Elastic cartilage is present in the tip of nose and ear pinna.
D. Calcified cartilage is not present in the pubis of pelvic girdle of frog

Answer

To solve the question regarding which statement is incorrect, we will analyze each statement one by one based on the information provided about different types of cartilage.

### Step-by-Step Solution:

1. **Analyze the First Statement**:
- The first statement claims that "hyaline cartilage lacks fibers and is present in sternum, hyoid and ribs."
- **Evaluation**: Hyaline cartilage does contain fine collagen fibers, although it lacks elastin fibers. It is indeed found in the sternum, hyoid, and ribs.
- **Conclusion**: This statement is **true**.

2. **Analyze the Second Statement**:
- The second statement states that "white fibrous cartilage is the strongest and is present in intervertebral discs."
- **Evaluation**: White fibrous cartilage is known to be the strongest type of cartilage and is present in the intervertebral discs and pubic symphysis.
- **Conclusion**: This statement is **true**.

3. **Analyze the Third Statement**:
- The third statement mentions that "elastic cartilage is present in the tip of the nose and ear pinna."
- **Evaluation**: Elastic cartilage is indeed found in non-load-bearing structures such as the ear (pinna) and the tip of the nose.
- **Conclusion**: This statement is **true**.

4. **Analyze the Fourth Statement**:
- The fourth statement claims that "calcified cartilage is not present in the pubis of pelvic girdle of frog."
- **Evaluation**: Calcified cartilage can occur in the pelvic girdle of frogs, particularly in the pubis. Therefore, this statement is incorrect.
- **Conclusion**: This statement is **false**.

### Final Answer:
The statement that is incorrect is: "Calcified cartilage is not present in the pubis of pelvic girdle of frog."

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