1. The question asks about the identity of Greta Thunberg. 2. Greta Thunberg is a Swedish environmental activist known for her efforts to combat climate change. 3. She gained international recognition for starting the "Fridays for Future" school strike movement. 4. Greta advocates for urgent action to reduce carbon emissions and address global warming. 5. This is a general knowledge question, not a math problem, so no formulas or calculations are involved.