Positive Charge Q Is Distributed Uniformly Throughout an Insulating Sphere $\pi$

Multiple Choice

Positive charge Q is distributed uniformly throughout an insulating sphere of radius R, centered at the origin. A particle with a positive charge Q is placed at x = 2R on the x axis. The magnitude of the electric field at x = R/2 on the x axis is:

A) Q/4 $\pi$$\varepsilon$ ₀R²
B) Q/8 $\pi$$\varepsilon$ ₀R²
C) 7Q/18 $\pi$$\varepsilon$ ₀/R²
D) 11Q/18 $\pi$$\varepsilon$ ₀R²
E) none of these