Euro III norms were stipulated to control

Options

A. carbon content
B. sulphur content
C. nitrogen content
D. phosphorus content

Answer

**Step-by-Step Solution:**

1. **Understanding Euro III Norms**: The Euro III norms refer to a set of regulations established by the European Union aimed at reducing harmful emissions from vehicles. These norms are part of a series of standards that have been progressively implemented to improve air quality.

2. **Identifying the Focus of Euro III Norms**: The primary goal of Euro III norms is to limit various pollutants emitted by vehicles. This includes controlling the emissions of substances like carbon monoxide, hydrocarbons, nitrogen oxides, and sulfur oxides.

3. **Analyzing the Options**:
- **Option 1: Carbon Content** - While carbon emissions are a concern, Euro III norms specifically target other pollutants more directly.
- **Option 2: Sulfur Content** - Euro III norms were indeed established to limit sulfur content in fuels, which helps in reducing sulfur dioxide emissions.
- **Option 3: Nitrogen Content** - Nitrogen oxides are regulated, but the primary focus of Euro III is not solely on nitrogen.
- **Option 4: Phosphorus Content** - Phosphorus is not a primary concern in the context of vehicle emissions.

4. **Conclusion**: Based on the analysis, the correct answer is that Euro III norms were stipulated to control **sulfur content**.

**Final Answer**: Euro III norms were stipulated to control sulfur content.

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