Spheres of Charge: the Graph in the Figure Shows the Electric

Spheres of charge: The graph in the figure shows the electric field strength (not the field lines) as a function of distance from the center for a pair of concentric uniformly charged spheres. Which of the following situations could the graph plausibly represent? (There may be more than one correct choice.)

A) a positively charged conducting sphere within another positively charged conducting sphere
B) a positively charged conducting sphere within an uncharged conducting sphere
C) a solid nonconducting sphere, uniformly charged throughout its volume, inside of a positively charged conducting sphere
D) a positively charged nonconducting thin-walled spherical shell inside of a positively charged conducting sphere
E) a positively charged nonconducting thin-walled spherical shell inside of another positively charged nonconducting thin-walled spherical shell