(we know A is not the right answer)

In step 4 of Station D, distilled water was added to the test tube. The color of the solution in the test tube after adding the distilled water is different from the color before the distilled water was added. Based on these observations, has a chemical or physical change occurred? chemical change: the water reacted with the contents of the test tube physical change; the water did not react with the contents of the test tube chemical change; a color change is always due to a chemical change physical change; a color change is always due to a physical change