Consider the force $F$ on a charge $q$ due to a uniformly charged spherical shell of radius $R$ carrying charge $Q$ distributed uniformly over it. Which one of the following statements is true for $F$,if $q$ is placed at distance $r$ from the centre of the shell?

• A
  $F = \frac{1}{4 \pi \varepsilon_{0}} \frac{Qq}{r^{2}}$ for $r > R$
• B
  $\frac{1}{4 \pi \varepsilon_{0}} \frac{qQ}{R^{2}} > F > 0$ for $r < R$
• C
  $F = \frac{1}{4 \pi \varepsilon_{0}} \frac{Qq}{r^{2}}$ for all $r$
• D
  $F = \frac{1}{4 \pi \varepsilon_{0}} \frac{Qq}{R^{2}}$ for $r < R$