Two charged particles are located on the $x-$axis, as shown in the figure above. One particle with a charge of $+Q$ is located at $x=0cm,$ and the other particle with a charge of $-Q$ is located at $x=4cm.$ Where can a third particle of charge $+4Q$ be located so that the net force on the particle at $x=4cm$ is zero?

$($A$)x=2cm$

$($B$)x=8cm$

$($C$)x=12cm$

$F_F=|||)/(16$

$=k\frac{|Q|}{16}$

$($D$)x=20cm$