Answer: (C) Scientists are questioning whether asteroids even hit the Earth and helped it form the water on it.
Step-by-step explanation:
The scientists are collecting evidence for the fact that the earth's water is the product of the gas left due to the formation of the sun and the asteroidal material. The fact finding inquiry related to this matter has also arose many questions related to the development of the other planets on the solar system and their potential to sustain or support life.
Hence, based on the above information, option C. is correct.