1. The problem asks which principle makes Chief Justice John Marshall's statement about the Constitution being adaptable to various crises true. 2. The options are due process, separation of powers, amendment process, and checks and balances. 3. Due process ensures fair treatment through the judicial system but does not directly address adaptability. 4. Separation of powers divides government into branches but does not itself provide a method for adapting the Constitution. 5. The amendment process allows the Constitution to be changed or updated to meet new challenges, directly supporting adaptability. 6. Checks and balances maintain balance among branches but do not change the Constitution. 7. Therefore, the amendment process is the principle that makes the Constitution adaptable to various crises. Final answer: amendment process