How Does a Computer System Know That a Sales Manager

Multiple Choice

How does a computer system know that a sales manager has authorised a credit transaction over $1000?

A) The input terminal has bio-security check eg retina scanning.
B) A combination of checks on the size of the credit required and the access rights of the manager when she logged in with her username and password
C) The system must insist on the sales manager entering the transaction
D) The control comes from the work practices outside the computer