The correct answer is:
D. There would likely not be life on Earth because its surface would be much colder and Earth's water would be frozen.
Without greenhouse gases, the Earth would not be able to trap heat effectively, leading to a much colder planet. This drop in temperature would result in most of the water on Earth freezing, making it extremely unlikely that life as we know it could survive. Greenhouse gases play a critical role in maintaining the Earth's temperature suitable for life by trapping heat from the Sun.