why are spheres A B AND C attracted to sphere D?

In the image:
D IS THE BIGGEST
A IS THE SMALLEST
B IS BIGGER THAN A BUT SMALLER THAN C
C IS BIGGER THAN B BUT SMALLER THAN D

Responses

D is closest to all three bodies.
D is closest to all three bodies.

D is the most massive of the four bodies.
D is the most massive of the four bodies.

of D's position with regard to the other three bodies.
of D's position with regard to the other three bodies.

D is the only body that is not moving in an orbit.
D is the only body that is not moving in an orbit.

(PICK AN ANSWER OPTION)

D is closest to all three bodies.