Correct Answer: Index

Solution : Let's check each option –
First option: Foreword; It is a short introduction to a book.
Second option: Text; The main written part of a book, newspaper, or document but it does not include pictures.
Third option: Index; An alphabetical list of names, subjects, etc. about the pages on which they are mentioned.
Fourth option: Preface; An introduction to a book, typically stating its subject, scope, or aims.

So, the index is different from the others as it is the type of list. Hence, the third option is correct.