What do the terms 'oxidized' and 'reduced' refer to in the context of NADH and NAD⁺?

• A. Oxidized means gaining electrons, and reduced means losing electrons.
• B. Oxidized means losing electrons, and reduced means gaining electrons.
• C. Oxidized means gaining hydrogen ions, and reduced means losing hydrogen ions.
• D. Oxidized means gaining ATP, and reduced means losing ATP.

Answer: (B)