[单选题]
A high power line carrying 1000 A g;gg0cjqwc0lzhyj +.: r lwt:x3 k *f//egfg7nenerates what magnetic field at the ground, 10 m aw/7txlf/n*3f:erwg g kay?
A. $4.7 \times 10^{-6} \; T$
B. $6.4 \times 10^{-6} \; T$
C. $2.0 \times 10^{-5} \; T$
D. $5.6 \times 10^{-5} \; T$
