Final answer:
Brown sugar can affect the stability of whipped egg whites, hence it is not recommended except when making Swiss Meringue, where the sugar and egg whites are heated together before whipping.
Step-by-step explanation:
The question whether brown sugar can be used for whipping egg whites has a specific answer. Using brown sugar in the traditional method of whipping egg whites can indeed affect the stability of the meringue because the molasses in the brown sugar can interfere with the formation of a stable foam. However, brown sugar can be successfully used in the Swiss Meringue method, where the sugar and egg whites are heated together before being whipped into a stable meringue. The answer to the question is, therefore, c) Only in Swiss Meringue.