What is a colonnade?

a. a kind of lintel
b. a series of arches
c. a type of roof design
d. a row of columns
e. none of these are correct

d. a row of columns

a. Incorrect. Though the post and lintel construction is essential in a colonnade, a lintel is not a kind of colonnade.
b. Incorrect. A series of arches is called an arcade.
c. Incorrect. A colonnade is not a type of roof design.
d. Correct. A colonnade is a row of columns and a common feature in classical architecture.
e. Incorrect. A colonnade is a row of columns and a common feature in classical architecture.