Steel is a mixture of:

Steel is fundamentally an alloy, which is a mixture of metals or a metal and another element. The correct answer is Iron and Carbon. Iron serves as the primary metallic component, and carbon is added to significantly enhance its strength, hardness, and durability. This combination creates a material with properties superior to pure iron.

• Iron and Oxygen would typically form iron oxides, commonly known as rust, which is a corrosive process, not steel.
• Carbon and Sulfur are not the primary components of steel; sulfur is often an undesirable impurity that can make steel brittle.
• Iron and Sulfur is incorrect because sulfur is generally considered a detrimental impurity in steel, negatively impacting its mechanical properties.