[单选题]
A metal sphere of radius 10 cm car e qx :nad/uwdg-4wf01ries a charge of +2.0 mC. wihdnqz8( zzj* (ba,3 What is the magnitude of the electric field 5.0 cm from the sphere's surfac(zw3 dq nzz*8ha(,bj ie?
A. $4.0 \times 10^{5} \; N/C$
B. $8.0 \times 10^{5} \; N/C$
C. $4.0 \times 10^{7} \; N/C$
D. $8.0 \times 10^{7} \; N/C$