What is composed of the legal rules, doctrines, and principles adopted by the courts?

The correct choice is case law, which is formed by the legal rules, doctrines, and principles established through judicial decisions in individual cases. When courts interpret statutes, apply legal precedents, or rule on legal disputes, they create case law that becomes binding or persuasive for future cases. This body of law is dynamic and evolves as courts reinterpret existing principles or address new legal issues.

Statutory law, in contrast, refers specifically to laws enacted by legislative bodies. While statutory law is important, it is not composed of judicial rulings but rather is established through formal legislative processes. Common law refers to the broader legal system that originated in England and is characterized by the reliance on precedent set by court decisions, making it closely related but not identical to case law. Regulatory law consists of rules created by administrative agencies and does not stem directly from court rulings. Thus, case law is the most precise answer as it directly pertains to the legal rules formed by courts.