Answer
$\bf{B}$
Work Step by Step
We know that the diagonals bisects each other. This means that the line segments of both diagonals are congruent.
$6x-7=3x+2$
or, $6x-3x=2+7$
or, $3x=9$
or, $x=3$
Next, $3y-6=y+4$
or, $3y-y=4+6$
or, $2y=10$
or, $y=5$
Therefore, the correct option is $\bf{B}$.
