The correct answer is "Compared to surgery or to chemicals used to treat cancer at the time, radium was much safer and more effective."
Explanation:
"Marie Curie and the Discovery of Radioactivity" describes the way Marie Curie and her husband discovered radiation through the discovery of Radium and Polonium elements, as well as, how this had an effect on the world.
One detail that shows this discovery was beneficial to humanity is "Compared to surgery or to chemicals used to treat cancer at the time, radium was much safer and more effective" because after Marie Curie discovery radiation became a the most effective and safest method to treat cancer as it reduced the growth of cancer cells and it was less invasive than surgery. Moreover, this use of radiation in medicine saved thousands of lives.
