If $K_{sp}$ of $CaF_2$ at $25\,^{\circ}C$ is $1.7 \times 10^{-10}$,the combination amongst the following which gives a precipitate of $CaF_2$ is

• A
  $1 \times 10^{-2} \, M \, Ca^{2+}$ and $1 \times 10^{-5} \, M \, F^{-}$
• B
  $1 \times 10^{-4} \, M \, Ca^{2+}$ and $1 \times 10^{-4} \, M \, F^{-}$
• C
  $1 \times 10^{-3} \, M \, Ca^{2+}$ and $1 \times 10^{-5} \, M \, F^{-}$
• D
  $1 \times 10^{-2} \, M \, Ca^{2+}$ and $1 \times 10^{-3} \, M \, F^{-}$