Read the following four statement (i) - (iv) having certain mistakes in two of them.
(i) Adipose tissue is a type of dense connective tissue located beneath the skin
(ii) Compound epithelium has extensive role in absorption and secretion
(iii) Most of the cartilages in vertebrate embryos are replaced by bones in adults
(iv) Smooth muscles are involuntary as their functioning cannot be directly controlled
Which of the above statements have mistakes ?

Options

A. (ii) and (iii)
B. (iii) and (iv)
C. (i) and (iii)
D. (i) and (ii)

Explanation

To determine which statements contain mistakes, we will analyze each statement one by one.

### Step 1: Analyze Statement (i)
**Statement (i)**: Adipose tissue is a type of dense connective tissue located beneath the skin.

- **Analysis**: Adipose tissue is primarily made up of fat cells and is classified as loose connective tissue, not dense connective tissue. It is indeed located beneath the skin, but the classification is incorrect.

**Conclusion**: Statement (i) is incorrect.

### Step 2: Analyze Statement (ii)
**Statement (ii)**: Compound epithelium has extensive role in absorption and secretion.

- **Analysis**: Compound epithelium consists of multiple layers of cells and primarily serves protective functions. It has a limited role in absorption and secretion compared to simple epithelium, which is specialized for these functions.

**Conclusion**: Statement (ii) is incorrect.

### Step 3: Analyze Statement (iii)
**Statement (iii)**: Most of the cartilages in vertebrate embryos are replaced by bones in adults.

- **Analysis**: This statement is correct. In vertebrate development, many cartilages present in embryos are indeed replaced by bone as the organism matures.

**Conclusion**: Statement (iii) is correct.

### Step 4: Analyze Statement (iv)
**Statement (iv)**: Smooth muscles are involuntary as their functioning cannot be directly controlled.

- **Analysis**: This statement is also correct. Smooth muscles are found in the walls of internal organs and operate involuntarily, meaning they are not under conscious control.

**Conclusion**: Statement (iv) is correct.

### Final Conclusion
The statements containing mistakes are:
- **Statement (i)**: Incorrect classification of adipose tissue.
- **Statement (ii)**: Misrepresentation of the role of compound epithelium.

### Summary of Mistakes
- **Incorrect Statements**: (i) and (ii)
- **Correct Statements**: (iii) and (iv)

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