The hardness of a transparent glass pane is tested by scratching it with a copper penny. The copper penny is unable to scratch the glass. The glass pane is then sandblasted to create patterns on its surface. After sandblasting, the hardness of the pane is tested using the same copper penny. Again, the copper penny does not scratch the glass. Which of the following sentences is true about the hardness of the glass pane?
A. It does not change because its thickness remains the same after sandblasting.
B. It changes because it undergoes a change in its mass after sandblasting.
C. It does not change because its chemical composition remains the same after sandblasting.
D. It changes because it undergoes a change in its transparency after sandblasting.