Final answer:
A scientist working on reducing the heating of Earth by limiting solar heat trapped in greenhouse gases is studying solar radiation management. This method is a part of a suite of strategies meant to mitigate global warming, which includes natural and technological approaches.
Step-by-step explanation:
The scientist studying methods to reduce Earth's heating by reducing the amount of solar heat trapped in greenhouse gases would be studying b. Solar radiation management.
Scientists looking into how to minimize the greenhouse effect typically explore various approaches, including but not limited to carbon sequestration, solar radiation management, renewable energy, and afforestation. Solar radiation management directly targets the reduction of solar heat absorption by the Earth's atmosphere and is aimed at mitigating the warming effects of greenhouse gases. To achieve this, scientists may investigate reflecting a portion of the sun's rays back into space, thus preventing them from warming the planet's surface.
Restoration of ecosystems, which can sequester carbon naturally, like through afforestation, becomes a form of geo-engineering on a planetary scale, as it involves managing land in a way that maximizes its capacity to absorb carbon, thereby reducing atmospheric CO2 levels. Both natural and technological methods fall under the broader umbrella of strategies designed to counteract climate change and global warming.