What do scientists study to reconstruct past climate conditions?
tree branches, pollen grains, and rain water
pollen grains, tree rings, and fossils
rain water, tree rings, and fossils
fossils, pollen grains, and tree branches
Fossils harms air because it releases so much CO2 (Carbondioxide) when it burns, and causes *greenhouse effect* and *climate changing* so scientists musn't do that for world's sake.
All of the options except the first include "fossils" so the answer would be A. (All of the options would have been correct if "fossils" wasn't in it.)
