Step-wise Solution:
Step 1: Understand the question:
The question is asking about the originator of the concept "Pure Theory of Law," which is a significant legal philosophy theory.
Step 2: Recall the contributions of each jurist:
- John Austin: Known for the "Command Theory of Law," where law is seen as commands issued by a sovereign.
- H. L. A. Hart: Introduced the "Concept of Law" and theories regarding primary and secondary rules.
- Hans Kelsen: Propounded the "Pure Theory of Law," aiming to separate law from morality, politics, and sociology, focusing purely on law as a system of norms.
- Jeremy Bentham: Founder of Utilitarianism in legal theory, advocating for laws based on the principle of utility (greatest happiness of the greatest number).
Step 3: Analyze the definition:
The "Pure Theory of Law" is directly associated with Hans Kelsen. His work emphasizes a normative approach, separating law from external influences and focusing on a hierarchical structure of norms (Grundnorm).
Step 4 (Final Answer): The correct answer is Option 3: Hans Kelsen.
✅ Final Answer: Hans Kelsen