Scientists have found that Mars has water ice at its poles, even though volcanic activity has never been observed on Mars. Would this prevent the inside-out model from becoming a theory?
A. Yes, because any comet that hit Earth also hit Mars.
B. Yes, because it shows that volcanic activity is necessary for a planet to have liquid water.
C. No, because no data from Mars is applicable to Earth.
D. No, because a single observation is not sufficient to discredit a theory.