A data analyst inputs the following command:

quartet $\%>\%$ group$\_$by$($set$)\%>\%$ summarize$($mean$($x$),$ sd$($x$),$ mean$($y$),$ sd$($y$),$ cor$($x$,$ y$)).$

Which of the functions in this command can help them determine how strongly related their variables are?

$1$ point

sd$($y$)$

mean$($y$)$

sd$($x$)$

cor$($x$,$y$)$