Final answer:
Line spectra is the best way to determine the temperature of a star.
Step-by-step explanation:
The best option to determine the temperature of a star is through line spectra. When light from a star passes through a prism, it produces a spectrum of colored lines. Each element in the star's atmosphere absorbs certain wavelengths of light, creating a unique pattern of lines. By analyzing these lines, astronomers can determine the temperature of the star.
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