In ServiceNow, to display data from another table within a form, the Reference field type is used. A Reference field creates a relationship between the current table and another table by storing a unique identifier (sys_id) of a record from the referenced table. This allows users to select a record from the referenced table and access its data within the form. Therefore, the correct answer is B.
The other field types do not provide this functionality:
* A. Phone Number: This field type is designed to store phone numbers and does not create relationships between tables.
* C. Date: This field type is used to store date values and does not reference records from other tables.
* D. String: This field type stores text strings and does not facilitate querying records from another table.
For more detailed information, refer to the official ServiceNow documentation on Field Types.