In which year did the sovereign grant transition from two tax-funded payments to one?

The correct response indicates that the transition to a single payment system for the sovereign grant occurred in 2011. This change was part of a broader reform aimed at modernizing the funding of the monarchy. Prior to 2011, the royal family received funding through two separate sources: the Civil List and the Grant-in-Aid. The switch to a single sovereign grant was intended to improve transparency and efficiency in how royal funding was structured, combining these payments into one annual payment calculated as a percentage of the income the Crown Estate generates. This reform simplified the funding process and increased accountability regarding how public money was used by the monarchy.

The other options represent years that do not align with this specific change, as the arrangement remained as it was prior to 2011, and subsequent years pertain to other adjustments or discussions regarding royal finances, but none involved the significant alteration made in 2011.