Final answer:
The most important factor in control effectiveness is the tone at the top, followed by clear policies regarding controls.
Step-by-step explanation:
The most important factor in control effectiveness is the tone at the top. The tone at the top refers to the ethical and moral behavior of top management in an organization. When top management sets a positive tone by prioritizing and demonstrating the importance of controls, it influences the entire organization to follow suit and take control responsibilities seriously.
Clear policies regarding controls are also vital for control effectiveness. They provide guidance and establish the framework for implementing controls throughout the organization. While an understanding of e-business networks and the use of random monitoring can enhance control effectiveness, they are not as crucial as clear policies and the tone at the top.