E) \( \mathrm{K}_{2} \mathrm{SO}_{4} \)

Did you know that potassium sulfate (\( \mathrm{K}_{2} \mathrm{SO}_{4} \)) has been used since ancient times as a fertilizer? Its history dates back to the early days of agriculture when farmers discovered that certain minerals could greatly enhance soil fertility. Today, it's widely utilized in the agricultural sector to supply essential nutrients to various crops, promoting healthy growth and increased yields. On the practical side, when applying \( \mathrm{K}_{2} \mathrm{SO}_{4} \), it's important to know the proper dosage. Common mistakes include over-application, which can lead to nutrient imbalances or salt stress in plants. Always conduct a soil test first to determine the right amount needed for your specific soil and crop type!