The Planet Mars

Out of all the planets in our solar system, Mars is the only one that has features similar to that of Earth. There is, therefore, a likelihood that life may exist there in the future. This is because of the similar tilt angles of both planets' rotational axes. Its seasons, as well as the nights and days, are similar to what we have on Earth. However, Mars has a thin atmosphere that doesn't allow it to trap any heat. So, its seasons are extreme. Therefore, the average temperature on Mars is much lower than that on Earth. The year on Mars is also twice as long as that on Earth because it is farther from the Sun than Earth. As a result, it takes longer to go around the Sun. It also has mountains, canyons, and deserts like those found on Earth. However, some of the volcanoes on Mars are 10 to 100 times bigger than those found on Earth. In particular, Olympus Mons, with a height of 16 miles, is the largest volcano in our solar system.
4
Which would be the best concluding sentence for this paragraph?
A.
These similarities and differences make the presence of life on Mars a possibility.
B.
Therefore, astronomers should be well equipped for extreme weather conditions.
C.
Therefore, the planet Mars is more unique and special than Earth.
D.
These similarities make us wonder why Mars is not called Earth II.