Answer:
Option b. Out of all the characteristics of stars, its color is the one that provides evidence that stars are black-body radiators.
Step-by-step explanation:
The term "black-body radiation" describes the relationship between an object temperature and the wavelength of electromagnetic radiation it emits. Stars act like black-bodies and this is why there are different colors of stars. A star's color depends on its surface temperature, while the cooler stars tend to more red in color, the hotter ones have more of a blue appearance, our Sun for instance, is in the mid-range of temperature therefore presenting a more white/yellow color.