Answer:
The colour of the metals
Explanation:
The colour of a metal is a qualitative property, because you can’t put a number to it.
A is wrong. Mass is a quantitative property, because you can measure it (e.g., 50 g).
B is wrong. Volume is a quantitative property, because you can measure it (e.g., 50 cm³).
C is wrong. You can measure the hardness of a substance on the Mohs scale, e.g., hardness of iron = 4.5).
