A geologist is comparing the properties of different minerals. He rubs each one on a piece of white tile and observes the color of the powder that is left behind. What type of test did he perform?

              Streak test is used to compare the properties of different minerals.  

Explanation:

                    Streak test is perform on rocks to check the properties of a mineral or rocks. If you have a piece of white floor tile, You can use it for the test. In this test we rub mineral on a piece of white tile Turn your tile so that the dull side faces up. Take your rocks one at a time and rub them back and forth over the surface of the tile and observe the color of the powder left behind which will tell about the type of mineral.

the correct option is option a