What criterion would you use in the LastName field to find records that do not contain a last name?

A) Is Null
B) "Null"
C) Is Not Null
D) No LastName

The criterion "Is Null" is the best choice because it selects all records where the LastName field is empty or contains a null value. This will give you a list of all records in which the last name is not mentioned. Option B is not correct because "Null" is a string value and not a null value. Option C will select all records that have a value in the LastName field, which is the opposite of what we want. Option D is not correct because it is not a valid criterion in Access.