Answer:
The Magna Carta
Step-by-step explanation:
The Magna Carta was created in 1215. Way before the documents listed on other options above. Before the creation of Magna Carta, Kings of England had unlimited power. They can create any forms of law they want and execute all people who dare to oppose them. Even without solid reasons/proof.
After This document was created, The Law was established as the highest power in the country. Even above the King. This massively limit the King's power and create a protection to citizens' right.