Analyzing Current and Historic Data Bout CO₂ Tells Us Current

Analyzing current and historic data bout CO₂ tells us current CO₂ levels _____________.

A) are lower than they have been in the past 2.7 million years
B) are only slightly higher than they have been in the past 2.7 million years
C) are the same as they have been for the past 100 years
D) are higher than they have been in the past 2.7 million years
E) We need more data to make any conclusions about the current CO₂ levels.