Question

the alveoli are built of... epithelial tissue. blood vessel connective tissue. all of these tissues. structural connective tissue.

Explanation:

Alveoli in the lungs are lined with simple squamous epithelial tissue, which allows for gas exchange. Blood vessel connective tissue (capillaries around alveoli) and structural connective tissue (supporting the alveolar structure) are also part of the alveolar - related tissues. So alveoli are built of all these tissues.

Alveoli have a lining of epithelial tissue (simple squamous epithelium for gas exchange), are surrounded by blood vessel connective tissue (capillaries for gas transport), and have structural connective tissue for support. So they are made of all these tissues.

Answer:

A. epithelial tissue. (Note: The correct answer should be "all of these tissues." as per the explanation. There was a mistake in the initial answer. The correct option is the one with "all of these tissues." So the correct answer is: