Task: Question Answering
Input (English): Background Paragraph: When you add sugar to a cold drink, you may stir it to help the sugar dissolve. If you don’t stir, the sugar may eventually dissolve, but it will take much longer. Stirring is one of several factors that affect how fast a solute dissolves in a solvent. Temperature is another factor. A solid solute dissolves faster at a higher temperature. For example, sugar dissolves faster in hot tea than in ice tea. A third factor that affects the rate of dissolving is the surface area of the solute. For example, if you put granulated sugar in a glass of ice tea, it will dissolve more quickly than the same amount of sugar in a cube. That’s because granulated sugar has much more surface area than a cube of sugar. You can see videos of all three factors at these URLs. 
Story: Justin is conducting a chemical experiment involving sodium hydroxide. A key part of the reaction is ensuring that the sodium hydroxide is dissolved in water before adding the other materials. Justin adds the sodium hydroxide to reaction A, and sets the heat to high. Justin can't use high heat for his second reaction, though, because the electricity supply is too weak to have both burners on high. Because of this, Justin adds the sodium hydroxide to reaction B and sets the heat to low. 
Question: In which reaction will the sodium hydroxide dissolve slower?
Output (English): reaction B.