$\"\"$

Let the coordinates of K be $\"\"$ .

Find the midpoint of $\"\"$ .

$\"\"$ (Midpoint point formula)

$\"\"$ (Substitute $\"\"$ )

$\"\"$ (Simplify) $\"\"$

Use $\"\"$ to determine the coordinates of K.

Since in a parallelogram diagonals bisect each other, $\"\"$ is the midpoint of $\"\"$ .

$\"\"$ (Midpoint of $\"\"$ is $\"\"$ )

Equate the coordinates

$\"\"$ $\"\"$

$\"\"$ (Simplify) $\"\"$

The coordinates of K are $\"\"$ $\"\"$

The option C is correct.