The correct answer is C. Joseph Priestley.
Neils Bohr was a Danish physicist who developed the Bohr model of the atom. William Ramsay was a Scottish chemist who discovered the noble gases. Ernest Rutherford was a New Zealand physicist who discovered the nucleus of the atom.
Joseph Priestley was an English chemist and theologian who is credited with the discovery of oxygen. He was also the first person to isolate carbon dioxide, ammonia, and nitrous oxide.
In 1774, Priestley was conducting experiments with a candle in a closed chamber when he noticed that a gas was produced that supported combustion better than air. He named this gas “dephlogisticated air” and believed that it was the pure form of air that was necessary for combustion.
In 1775, Priestley published a paper describing his discovery of dephlogisticated air. However, he did not receive much recognition for his work until after the French chemist Antoine Lavoisier showed that dephlogisticated air was actually oxygen.
Priestley’s discovery of oxygen was a major breakthrough in chemistry. It helped to explain the process of combustion and led to the development of new theories about the nature of matter.