[单选题]
How fast would a rocket ship have to move to hifr1k*90-n 9vr 6.izfepetm cog+c;1y uy kjle6s:8xv.mb 3d .wq,eylntract to half of its proper length (as observed by a stationag by .v. ,sxmyewu:yqe +8;k6 d3jllc1ry object)?
A. $0.50 \; c$
B. $0.65 \; c$
C. $0.78 \; c$
D. $0.87 \; c$
