[单选题]
A high power line carrying 1000 A generates what magneti3px(z6su yhz2t:8q hgc fi2dt2o8u5w/yl t(n i fteld at the ground, 1/ yt 28i5dlw( 2onuftt0 m away?
A. $4.7 \times 10^{-6} \; T$
B. $6.4 \times 10^{-6} \; T$
C. $2.0 \times 10^{-5} \; T$
D. $5.6 \times 10^{-5} \; T$
