You are creating a database that will store usernames and credit card numbers for an application.
You need to recommend a solution to store and reuse the credit card numbers in the database.
What should you recommend? More than one answer choice may achieve the goal. Select the BEST answer.

A.
Data encryption

B.
Transparent Data Encryption (TDE)

C.
Encrypting File System (EPS)

D.
Data hashing

Explanation:
If we are going to encrypt credit card number for storage, then we should have Data Encryption Key (DEK) for
encrypting the credit card number.
http://msdn.microsoft.com/en-us/library/bb934049.aspx