Answer:
The correct answer is - a) use the acid test.
Explanation:
In this chart, there are many minerals that share different properties with one another such as hardness, color, and luster of the minerals so on the basis of physical properties the group of students can not be sure if the given mineral is calcite or not.
To be sure if the given mineral is calcite the group of students must test the acid test which is specific for the calcite and if the test produces bubbles it is confirmed that the given mineral among these minerals is calcite.