The correct answers are B) ice core samples and C) tree rings.
Evidence of climate changes and conditions that affected early societies are gathered from ice core samples and tree rings.
As trees live for hundreds of thousands of years, they keep track of the climate change on Earth. The tree captures the environmental conditions of humidity, cold times, hot years, and fires. It can be shown in the tree rings and that is how scientists can learn about the change in the weather.
The same happens with ice-score records. These show that change in the weather on Earth is permanent. These records come from glaciers at the top of mountains and ice caps form the South and North Poles.