What Is the Drawback of Using Social Security Number (SSN)

Multiple Choice

What is the drawback of using Social Security Number (SSN) as the primary keys for tables of employees, hospital patients, students, and even cable TV customers?

A) typing the nine digit SSN numbers is laborious and time consuming
B) non-U.S. citizens may not have a SSN
C) it is not a confidential identification number
D) it is not a unique identification number