To find employee records that do not contain an entry in the Email field, use the _____ criterion in the Email field.

A) Is Not Null
B) Is Null
C) Find Unmatched
D) Is Blank

The correct choice is B, "Is Null". This criterion will return all employee records where the Email field is empty or has no value entered. "Is Not Null" would return all employee records where the Email field contains a value, which is not what we want. "Find Unmatched" is used to compare two tables and find records that do not match, so it is not applicable in this scenario. "Is Blank" is not a valid criterion in most database systems.