Answer: Option (D) is the correct answer.
Step-by-step explanation:
It is known that 1 centimeter contains 10 millimeter. Therefore, unit millimeter (mm) is smaller than centimeter (cm).
So, when different substances were dissolved in water then according to the given chart, substance which shows smallest number in millimeters will have the greatest solubility.
Thus, we can conclude that substance Z has the greatest solubility.