The Payment Card Industry Data Security Standard $($PCI DSS$)$ created by Visa, MasterCard, American Express, and Discover is a $\_\_\_\_\_\_\_\_\_\_.$

Set of voluntary security guidelines for retailers who accept Visa, MasterCard, American Express, and Discover credit cards.

Set of industry standards required for all online merchants that store, process, or transmit cardholder data.

Set of regulations $($that vary from state to state, and country to country$)$ that apply to credit card companies.

Set of standards required by U$.$S$.$ and international law for protecting credit card transaction data.