Explanation:

Though scientists have found no proof of past or present life on Mars,  from the cumulative evidence it is believed that during the ancient Noachian time period, there was liquid water on Mars and may have been habitable for microorganisms. Further, studies have found that Mars is similar to the early Earth as it has a cold climate and lacks plate tectonics or continental drift. Recently (September 2017), the Curiosity rover sent by NASA has detected boron on Mars which was an essential ingredient for life on Earth. This finding, along with the earlier discovery of liquid water on ancient Mars supports the possibility of early life on Mars. Hence option 3rd is correct.