Which 1967 treaty, ratified by over 100 nations including the two main space powers, prohibits the placement of nuclear weapons in orbit and declares celestial bodies the 'province of all mankind'?

• A The Moon Agreement
• B The Registration Convention
• C The Outer Space Treaty ✓
• D The Rescue Agreement

Formally the 'Treaty on Principles Governing the Activities of States in the Exploration and Use of Outer Space', it was signed in 1967 and forms the foundation of international space law.