How many different types of phone numbers are listed in the Glossary?

• A. 2 types: Internal and External
• B. 3, Internal, Callback, and External
• C. 4: Internal, External, Callback, and Fax
• D. 1: Internal

Answer: (B)

Three types are defined for phone numbers in the Glossary: Internal, Callback, and External. This is the count because those are the only categories the Glossary uses to describe phone numbers. Fax is not listed as its own type, so it isn’t counted among the types.