Benedict's solution is used to test for which substance, and what is the color change that indicates presence of sugar?

• A. It tests for starch; color changes to purple
• B. It tests for protein; color changes to violet
• C. It tests for lipids; color changes to pink
• D. It tests for sugar; color changes from light blue to green, yellow, orange, or red

Answer: (D)

Benedict's test is used to detect reducing sugars. The reagent contains copper(II) ions, and when a reducing sugar is present and the mixture is heated, the sugar donates electrons and reduces Cu2+ to Cu+. This change produces a visible color shift in the solution. If no sugar is present, the solution stays blue; with increasing amounts of sugar, the color moves through green, yellow, orange, and finally red as the concentration rises. That color progression is how you gauge the presence and approximate amount of sugar. This aligns with the option stating it tests for sugar and changes from light blue to green, yellow, orange, or red.