Answer:
D or A its up to u i know its not b or c cuz im not dumb UwU
Explanation:
D, light can travel in the air or a vacuum and the speed is constant whether the light source is stationary or moving.
Claro que yo no sabo como Hacer eso
Evidence supporting the Big Bang theory includes the presence of cosmic microwave background radiation, visual observation of redshifted objects and the abundance of primordial elements found throughout the universe.