Which of the following statements is/are not correct regarding connective tissues ?
(i) They are most abundant and widely distributed in the body of complex animals
(ii) They connect and support other tissues
(iii) They include diverse tissues such as bones, cartilage, tendons, adipose and other loose connective tissues.
(iv) They form the internal and external lining of many organs
(v) In all connective tissues except blood, the cells secrete fibres of structural proteins like collagen and elastin.

Options

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

Explanation

To determine which statements regarding connective tissues are not correct, we will analyze each statement one by one.

1. **Statement (i)**: "They are most abundant and widely distributed in the body of complex animals."
- **Analysis**: This statement is true. Connective tissues are indeed the most abundant and widely distributed tissues in complex animals, including humans.

2. **Statement (ii)**: "They connect and support other tissues."
- **Analysis**: This statement is also true. The primary function of connective tissues is to connect and support other tissues and organs in the body.

3. **Statement (iii)**: "They include diverse tissues such as bones, cartilage, tendons, adipose and other loose connective tissues."
- **Analysis**: This statement is true as well. Connective tissues are diverse and include various types such as bone, cartilage, tendons, and adipose tissue.

4. **Statement (iv)**: "They form the internal and external lining of many organs."
- **Analysis**: This statement is not correct. Connective tissues do not form the lining of organs; that function is primarily performed by epithelial tissues. Therefore, this statement is false.

5. **Statement (v)**: "In all connective tissues except blood, the cells secrete fibres of structural proteins like collagen and elastin."
- **Analysis**: This statement is true. All connective tissues, except for blood (which is a fluid connective tissue), secrete fibers such as collagen and elastin.

**Conclusion**: The only incorrect statement regarding connective tissues is statement (iv).

**Final Answer**: The statement that is not correct regarding connective tissues is (iv).

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