[单选题]
An index of refractidx 1tpdui.8m6 n.ywyanvc 8:7on less thab;*x x8 6hynemn one for a medium would imply
A. that the speed of light in the medium is the same as the speed of light in vacuum.
B. that the speed of light in the medium is greater than the speed of light in vacuum.
C. refraction is not possible.
D. reflection is not possible.