[单选题]
On a day when the speed of sound in e9f,.lmaebf r/ f 6mr,w3mr.f air is 340 m/s, a bat emits 7h 9q l,kq(k ce-hlw.ua shriek whose echo reaches it 0.0250 s later. How far away was the object7k9lqch,(k lw eu.q h- that reflected back the sound?
A. $4.25 \; m$
B. $8.50 \; m$
C. $0.425 \; m$
D. $0.850 \; m$
