Which of the following laws is the cornerstone of many U$.$S$.$ computer$-$related federal laws and enforcement efforts and formally criminalizes $$accessing a computer without authorization or exceeding authorized access$$ for systems that contain information of national interest as determined by the U$.$S$.$ government?

a$.$ Health Information Technology for Economic and Clinical Health $($HITECH$)$ Act of $2009$

b$.$ Electronic Communications Privacy Act $($ECPA$)$ of $1986$

c$.$ Computer Fraud and Abuse $($CFA$)$ Act of $1986$

d$.$ Sarbanes$-$Oxley $($SOX$)$ Act of $2002$