If atmospheric CO2 concentrations increase twofold or more, how will plants be affected, disregarding any changes in climate?
A) All plants will experience increased rates of photosynthesis.
B) C3 plants will have faster growth; C4 plants will be minimally affected.
C) C4 plants will have faster growth; C3 plants will be minimally affected.
D) C3 plants will have faster growth; C4 plants will have slower growth.
E) Plant growth will not be affected because atmospheric CO2 concentrations are never limiting for plant growth.
