What changes were made to the Freon system in the B737-8200?

The choice regarding two nozzles directed at the waste bin is correct because this change enhances the effectiveness of the waste management system onboard the B737-8200. By directing cooling from the Freon system specifically towards the waste bin, the aircraft can better manage odor control and maintain sanitation within the lavatory area. This adjustment demonstrates a focus on passenger comfort and hygiene, which are critical elements in modern aircraft design.

The other options do not address relevant improvements made to the Freon system in the B737-8200. Increasing the number of nozzles aimed at the water heater or removing nozzles would not effectively enhance the efficacy of waste management, nor would merely increasing the capacity of the Freon tank necessarily translate to better performance or passenger experience.