Science and Technology · Space Exploration

Consider the following statements about the Viking lander experiments on Mars and their interpretation: I. The Viking 1976 lander metabolic experiment reported initial signs of metabolism, but a different detector on the same mission found no organic molecules in the soil. II. The Viking metabolic result is universally accepted today as incontrovertible evidence of microbial life on Mars. III. Later analyses suggested that non-biological oxidants in the Martian soil (like perchlorates) and experimental artifacts could explain the Viking positive responses without invoking life. Which of the following options is correct?