Pseudostratified epithelium is found in

The type of epithelium that forms the inner lining of blood vessels is ..........

$A$ student was given a sample of tissue. He observes and concludes the following characters.
$(i)$ The cells are composed of a single layer of tall and slender cells.
$(ii)$ Their nuclei are located at the base.
$(iii)$ Free surface may have microvilli.
$(iv)$ It is found in the lining of stomach and intestine.
$(v)$ They help in secretion and absorption. Based on the above features identify the epithelium.

In which of the following are columnar epithelial cells with microvilli or a brush-like border found?

Which insoluble protein is present in scales?

Select the correct match.