To determine how much the Earth's climate has warmed over the last 100 years, we need to consider the historical data and scientific consensus on this issue.
1. We know that the Earth's climate is influenced by various factors, including greenhouse gas emissions, deforestation, and pollution, which have led to global warming.
2. Climatologists and researchers have been studying temperature records over the past century to estimate the increase in global average temperatures.
3. According to the most accurate data available, the Earth's climate has warmed by approximately 1.0°C over the last 100 years.
Thus, the correct answer is:
O C. 1.0°C
