Answer:
Conference
Explanation:
Congressional leaders form CONFERENCE committees when they want to take up an issue that falls between the jurisdiction of existing committees, to highlight an issue, or to investigate a particular problem.
A topic for an astronomy paper can be the life cycle of a star.
The main way in which the separation of powers guards against tyranny is by making it impossible for any single branch to become too powerful, since each branch "checks and balances" the others out when it comes to making and enforcing legislation.