Q7. Which one of the following represents the correct order of ionic radii among K^+, S^{2-}, Cl^- and Ca^{2+}?
- (a) Ca^{2+} > K^+ > Cl^- > S^{2-}
- (b) S^{2-} > CI^{-} > K^{+} > Ca^{2+}
- (c) Cl^{-} > S^{2-} > K^{+} > Ca^{2+}
- (d) K^+ > Ca^{2+} > S^{2-} > Cl^-