[单选题]
A cyclist does work at the rate of 500 W while ridinx 186um1w ukk9ekgu+h g. How much force does her soiwteb9;5 alr) vv27 foot push with whene v9w7a ;l25i rb)tvos she is traveling at 8.0 m/s?
A. $31 \; N$
B. $63 \; N$
C. $80 \; N$
D. $4000 \; N$
