The Open Web Application Security Project $($OWASP$)$ Top Ten is a list of web application security threats that is composed by a member$-$driven OWASP committee of application development experts and published approximately every $24$ months. What is probably the single most important way of countering the highest number of items on the OWASP Top Ten $($regardless of year$)?$

social engineering training

disciplined coding practices and processes

white$-$box source code testing

physical control at all locations at which the application is eventually used.