12. A solid nonconducting sphere of radius R carries a charge Q distributed uniformly throughout its volume. At a certain distance r₁ (r₁ ＜ R) from the center of the sphere, the electric field has magnitude E. If the same charge Q were distributed uniformly throughout a sphere of radius 3R, the magnitude of the electric field at the same distance r₁ from the center would be equal to
(A) E/9
(B) E/3
(C) 3E
(D) 9E

(E) E

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