The authorities explained the need for compliance with all regulations. Compliance most nearly means:
Choice "4" is the one to pick here. "Compliance" most nearly means obedience. If you're compliant with the rules of your school, it means that you have obeyed its rules. "Defiance" can be eliminated because "authorities" don't generally recommend it with regard to their regulations. That would be like the principal of your high school telling you to defy all school rules.