[单选题]
One of Einstein's postulates in formulating the sp6vmq f:b (m) cmhvf.3mecial theory of re:/-kjsrqc -eelativity was that the laws of physics are the same in rerk:ce j/sq -e-ference frames that
A. accelerate.
B. move at constant velocity with respect to an inertial frame.
C. oscillate.
D. are stationary, but not in moving frames.
