Which of the following is considered a major mineral?

Calcium is classified as a major mineral because it is essential for numerous vital functions in the body and is required by the body in larger amounts compared to trace minerals. Major minerals, also referred to as macrominerals, include those that are needed in significant quantities—typically more than 100 mg per day. Calcium plays a critical role in maintaining bone health, facilitating muscle contraction, transmitting nerve impulses, and aiding in blood clotting.

Sodium, while also a major mineral, is not the correct answer here, as the question may be focused on calcium as it is often highlighted for its well-known importance in nutrition. Iron is classified as a trace mineral, even though it is crucial for health, particularly in oxygen transport and energy production. Chromium, similar to iron, is categorized as a trace mineral, which means it is required in smaller amounts by the body.