Which of the following establishes the process for amending the Illinois Constitution?

The correct answer describes the process for amending the Illinois Constitution as requiring a two-thirds vote in the General Assembly. This method ensures that a significant majority of elected representatives agree on the proposed amendment, reflecting a broad consensus before any changes are made to the foundational legal document of the state.

This process is intentionally designed to safeguard the integrity of the Constitution, preventing hasty modifications and requiring a level of bipartisan support that is crucial for constitutional changes. It emphasizes the importance of legislative agreement, which is a hallmark of democratic governance.

The other options do not accurately represent the amendment process as outlined in the Illinois Constitution. For example, a simple majority would not provide the necessary safeguards or checks against potential fleeting political pressures, while a convention called by the public is not a standard part of the amendment process in Illinois. Additionally, a unanimous decision by the Supreme Court is not relevant to constitutional amendments, as judicial interpretation does not impose constitutional changes – that power lies within the legislative process representative of the people's will.