[单选题]
If a material has an index of refraction of 1.50, what i*+dsozz gih//.fv y-a s the speed of ligh/tiyo fjph213 , zb bf3+wyjp3-4kyxit through tj,fo x-yfji 3yp kbpz4b2+31yh/iw3it?
A. $2.00 \times 10^{8} \; m/s$
B. $3.00 \times 10^{8} \; m/s$
C. $4.50 \times 10^{8} \; m/s$
D. $6.00 \times 10^{8} \; m/s$
