Solution : Option (a) will qualify as a database as dictionary is a database of different words with their meanings stored in it. Option (b) will qualify as a database as telephone directory contains data regarding people like their name, address, phone number. Option (c) will qualify as a database as rolodex is a file that contains cards holding information about people like names, addresses and phone numbers. Option (d) will not qualify as a database as textbook index only points to the topics in the book, it itself does not store any data in it related to the topic or anything..