Who is Jöns Jakob Berzelius?

• A. Jöns Jakob Berzelius
• B. Antoine Lavoisier
• C. Dmitri Mendeleev
• D. Marie Curie

Answer: (A)

Berzelius was a Swedish chemist who helped shape modern chemistry by establishing the system of chemical symbols we use for elements, like H for hydrogen and O for oxygen. He also contributed to understanding elements and atomic weights, which underpins how chemists write formulas. This makes recognizing his name the best choice, since the question asks who he is. The other figures are famous for different contributions: Lavoisier for the conservation of mass, Mendeleev for the periodic table, and Curie for pioneering work on radioactivity.