Answer:
Spiral Galaxies, Elliptical Galaxies & Irregular Galaxies
Explanation:
How did galaxies originate? Astronomers believe that after the big bang, the explosion which began the universe 10 billion to 20 billion years ago, gravity began to compress masses of free-floating gas. Two main theories, bottom-up and top-down, explain what happened next. According to bottom-up theories, clusters began to form and assembled together into the larger units we know as galaxies. Top-down theories suggest that galaxies formed first, and the stars and other objects within them were subsequently produced. They categorized different galaxies to maintain their tests from the other galaxies.
D. They come from other living things
Explanation:
The cell theory states that all living things come from preexisting cells.
The correct answer is option C, species evolve rapidly
Reason -
In adaptive radiation, the ancestral species diversifies at a fast rate and results into new species which have resulted due to changing climatic and environmental conditions. For example the mammals, reptiles, birds etc. all evolved from the dinosaurs after their extinction. The major impacts of adaptive radiation can be visualized when an organism moves to a new area and therefore transforms to survive.
