ANS:A - increased

Forward and backward feed are terms often used in the context of distillation processes. Forward feed involves introducing the hot feed into the column at a point above the feed tray, while backward feed involves introducing the hot feed below the feed tray. Typically, forward feeding is used when the feed is hotter than the average temperature in the column, while backward feeding is used when the feed is cooler. In terms of energy efficiency or economy, forward feeding generally results in increased energy savings. This is because forward feeding allows the hot feed to provide additional heat to the rising vapor, leading to better separation efficiency and potentially reduced energy consumption for reboiling. So, the correct answer is: "increased"