Final answer:
Analyzing the most abundant elements in the cosmos provides comprehensive insights into cosmic evolution, stellar processes, and the potential for habitable environments, largely due to the role of stars in forging these elements.
Step-by-step explanation:
By analyzing the most abundant elements in the universe, the Milky Way, our solar system, and on Earth, we gain D) All of the above: A) Insights into cosmic evolution and planetary formation, B) Understanding of stellar processes, and C) Inference about habitable environments. The distribution of elements like hydrogen, helium, carbon, calcium, and oxygen can tell us how the universe has evolved over billions of years into a structure that supports life. These elements were forged inside stars, the 'nuclear furnaces' that shaped much of the observable cosmos. By studying the abundance and location of heavy elements, we learn about star formation, the history of the Milky Way, and the origins of our solar system and Earth. Patterns in our solar system's formation can also suggest broader principles of planetary formation that may apply across the cosmos.