In $2004,$ a large department store chain in Germany was forced to withdraw customer loyalty c discovered that the company had secreted radio$-$frequency identification $($RFID$)$ tags in the plat in a wallet or purse, these cards can transmit information over distances of about a meter, and them to track which departments the customer visited. At issue was which data security issue?

unauthorized access

chat rooms

sexual innuendoes expressed through lewd humor

biometrics

consumer privacy