Steel slag can be the material for which of the following? 1. Construction of base road 2. Improvement of agricultural soil 3. Production of cement Select the correct answer using the code given below:

Steel slag is a valuable by-product of the steelmaking process, and its utilization in various applications contributes to resource efficiency and waste management. All three options listed are indeed valid uses for steel slag:

1. Construction of base road: Steel slag possesses good binding properties, durability, and strength, making it an excellent aggregate material for road construction, particularly in the base and sub-base layers. Its use can reduce the demand for natural aggregates and provide a sustainable alternative.

2. Improvement of agricultural soil: Steel slag contains essential plant nutrients such as calcium, magnesium, iron, and phosphorus. When applied to agricultural land, especially acidic soils, it can act as a liming agent, neutralize soil acidity, improve soil structure, and provide micronutrients, thereby enhancing soil fertility and crop yield.

3. Production of cement: Steel slag can be used as a supplementary cementitious material, either as a clinker substitute or as an aggregate in cement and concrete production. Incorporating slag helps reduce the clinker content in cement, which in turn lowers the energy consumption and carbon dioxide emissions associated with cement manufacturing, making it a more environmentally friendly option.

Given its versatility and beneficial properties, steel slag is utilized across these diverse sectors, contributing to a circular economy.