Define "revenue bills" under the Illinois Constitution.

Revenue bills are defined under the Illinois Constitution as those that involve the raising of money through taxes. This designation is crucial because it sets the framework for how the state can generate its income to fund various operations and services. Revenue bills typically deal with the imposition, amendment, or repeal of taxes, thus directly impacting the state's fiscal policies and budget.

The distinction of revenue bills is significant within legislative processes. Specifically, in Illinois, these bills must originate in the House of Representatives, which reflects the constitutional principle that taxation and revenue generation should be closely aligned with the representatives of the people. The other choices do not fully encompass the primary function of revenue bills. Allocating funding to public programs relates more to appropriations than to the raising of funds, while regulating spending limits does not pertain to revenue generation directly. Establishing tax exemptions, although related to taxes, does not fit the core definition of how the state raises revenue.