The Arabian Nights (1) / are indeed (2) / an interesting book. (3) / No error (4)

Options

A. 1 The Arabian Nights
B. 2 are indeed
C. 3 an interesting book.
D. 4 No error

Answer

2

Explanation

is will replace are because -
The Arabian Nights is the name of a book and a Singular Verb is used with name of nation/organisation/ book/film as in
The United Nations is head-quartered in New York.
Hence, is indeed is the right usage