The Increase in the Concentration of CO₂ in Earth's Atmosphere

The increase in the concentration of CO₂ in Earth's atmosphere over the past 100 years

A) results from a decrease in the rate of CO₂ uptake by photosynthesis.
B) is primarily caused by the burning of fossil fuels by humans.
C) will likely decrease the average temperature on Earth.
D) will result in lower sea levels.
E) is very slow.