Iron, sodium, and potassium are examples of what type of elements?

• A. Organic
• B. Inorganic
• C. Biochemical
• D. Physical

Answer: (B)

Inorganic refers to elements or compounds that do not form carbon–hydrogen (carbon-based) frameworks. Iron, sodium, and potassium are metals/ions that exist as simple elements or ionic forms and are considered inorganic minerals. They’re essential nutrients in biology, but their chemical nature isn’t carbon-based, which is why they don’t fit the organic category. The other options don’t describe a type of element: organic would imply carbon-containing compounds, while biochemical and physical aren’t classifications for elements themselves.