### Instruction: For a positive constant $c,$ in spherical coordinates $(\rho,\theta,\phi),$ find the shape described by the equation
\[\rho = c.\](A) Line
(B) Circle
(C) Plane
(D) Sphere
(E) Cylinder
(F) Cone

Enter the letter of the correct option.### Response: Ok, so in spherical coordinates, $\rho$ represents the distance from the origin.
So this equation is saying that $\rho$ is always equal to $c$.
Right. So this is the set of all points that are a distance of $c$ from the origin.
Which is a sphere.