Strengthening Argument for EV Adoption

In recent discussions about reducing carbon emissions, environmental policy expert Dr. Maria Brooks argues that incentivizing electric vehicle (EV) adoption will substantially decrease greenhouse gas emissions from the transportation sector. She highlights that countries with generous tax rebates for EV buyers have seen a notable uptick in sales, and consequently, a decrease in fossil fuel consumption. Some skeptics counter that merely increasing EV sales does not ensure a significant drop in overall emissions, as the environmental impact also depends on the energy sources used to charge these vehicles.

To strengthen Dr. Brooks' argument, which of the following would provide the most supportive evidence?