What substances are formed by galvanic current when it passes through the human body?

When galvanic current, which is a direct current, passes through the human body, it can lead to electrolysis of bodily fluids. Specifically, the passage of current through water and other electrolyte solutions in the body results in the formation of chemical compounds.

The correct answer refers to the electrolysis of water that occurs in the presence of sodium ions, producing sodium hydroxide and hydrogen gas. Sodium hydroxide is an alkali that can be formed when sodium (from electrolytes in the body) reacts with hydroxide ions derived from the breakdown of water. Hydrogen gas is also produced due to the reduction reactions occurring at the cathode.

Other options do present possible chemical reactions, but they do not accurately reflect the substances primarily involved when galvanic current is utilized in or through the human body. Therefore, sodium hydroxide and hydrogen gas are the expected products resulting from this specific electrochemical process.