Which detail from the article illustrates that not all of the Marfa lights are caused by
headlights from a nearby highway?
A The balls of light remain motionless and pulse on and off, switching from faint to bright.
B Robert Ellison saw the Marfa lights in 1883 while driving cattle, before cars
were invented.
C The lights are the size of soccer balls in bright colors of red, orange, green, blue,
white, or yellow.
D There are too many conflicting theories, so there will never be a definitive answer about
their origin.