Which topic would an astronomer most likely research?

formation of hurricanes
formation of coral reef ecosystems
formation of mountains on Earth
formation of canyons on Mars

An astronomer would most likely research formation of canyons on Mars

An astronomer would most likely research Canyons and Mars!
Think about breaking down the word, Astro like space!
Astronauts and astronomy both start with Astro. So in this case, astronomers would most likely research canyons and mars

Very hard to understand