[单选题]
Two point charges, initol 6y9ru:w6xn) ump5o q/;e2p:yztdp9 -vkqbially 2.0 cm apart, experience a 1.ynul tg0xh/j 4j0, cmve,1a8 z0-N force. If they are moved to a new separation of 8.0 cm, what ilm4aun0 c/jv1hx, ,eyt 8j g0zs the electric force between them?
A. $4.0 \; N$
B. $16 \; N$
C. $1/4 \; N$
D. $1/16 \; N$