Which of the following statements about spectral types of stars is true?
A) The spectral type of a star can be used to determine its surface temperature.
B) The spectral type of a star can be used to determine its color.
C) A star with spectral type A is cooler than a star with spectral type B.
D) A star with spectral type F2 is hotter than a star with spectral type F3.
E) All of the above are true.
Answer: E