Answer:
The correct answer is "dictionary"
Explanation:
A dictionary is a book where you will find the meaning of words listed alphabetically.
An enclyclopedia on the other hand is a book that gives information on different subjects and is ordered alphabetically.
An index lists names or subjects within a book and is ordered alphabetically
A table of contents lists chapter o section titles in a book.
So, the best option to find out the meaning of an unknown word is a dictionary.
