Some students investigated the effect of temperature on the digestion of starch to form maltose. They added equal volumes of amylase and starch solution to a number of test-tubes. The test-tubes were left for 30 minutes at a range of temperatures between 10°C and 60°C. They then measured the concentration of starch in each test-tube. Which graph was produced from these results? [Graphs A, B, C, D]

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