he five essential components established by the Committee of Sponsoring Organizations of the Treadway Commission

I need to choose one of these and explain why it is the most essential.  Also, I need 4 quality references all current (2015-2018) and used in the explanation.

The five essential components established by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) are control environment, risk assessment, control activities, information and communication, and monitoring.