Two springs $X$ and $Y$ undergo elastic extension. The graphs illustrate how the force $F$ applied to each spring changes with extension $x$. Which of the following statements is correct?
- AWhen each spring is given the same extension, the energy stored in $Y$ is $4$ times the energy stored in $X$.
- BWhen each spring is given the same extension, the energy stored in $Y$ is $8$ times the energy stored in $X$.
- CWhen the same force is applied to each spring, the energy stored in $Y$ is $4$ times the energy stored in $X$.
- DWhen the same force is applied to each spring, the energy stored in $Y$ is $8$ times the energy stored in $X$.