Identify the word or phrase that should be in italics.

Riding the Orient Express toward Istanbul, Tom read the novels of Mark Twain.
a. Orient Express
b. Istanbul
c. Mark Twain
d. none

a. Orient Express

The word that should be in italics is "Orient Express." Therefore, the correct answer is option a. Orient Express.

The correct answer is c. Mark Twain. When mentioning the title of a book, it should be italicized. In this sentence, "the novels of Mark Twain" is referring to a collection of books written by Mark Twain, so "Mark Twain" should be in italics.