Too complex?

Let Z denote any complex number of the type $x + iy$ in the complex plane. Then $\displaystyle |Z - \left( 3 + 4i \right) | + |Z - \left( 15 + 9i \right) | = K$ where K is any real number, represents

$$ A. Ellipse when $K = 13$

$$ B. Ellipse when $K > 13$

$$ C. A line segment when $K = 13$

$$ D. A circle.

How many of the above statements are correct?