Approximately what percentage of today's power is produced from nuclear generation?

Nuclear power generation accounts for a significant portion of the electricity produced worldwide. As of recent data, approximately 20% of the electricity used in the United States is generated from nuclear sources. This figure can vary by country, but in many developed nations, nuclear power reliably contributes between 15% to 30% of the total energy mix. The importance of nuclear energy lies in its ability to provide large amounts of baseload power with low greenhouse gas emissions once operational, making it a key player in the energy landscape, especially as efforts to combat climate change intensify.

This context underlines why the figure of 20% is the most accurate and relevant choice from the options provided.