Answer:
Telephone numbers need to be stored as a text/string data type because they often begin with a 0 and if they were stored as an integer then the leading zero would be discounted.
The other reason is that you are never likely to want to add or multiply telephone numbers so there is no reason to store it as an integer data type.
Step-by-step explanation:
A text data type can hold any letter, number, symbol or punctuation mark. It is sometimes referred to as 'alphanumeric' or 'string'.
The data can be pure text or a combination of text, numbers and symbols.
People often assume that a telephone number would be stored as an 'integer' data type. After all, they do look like numbers don't they!