Elevated Atmospheric CO₂ Concentration Results in Higher Rates of Plant

Elevated atmospheric CO₂ concentration results in higher rates of plant photosynthesis.It also increases the plants' carbon-to-nitrogen ratio, causing a "nitrogen dilution" effect that decreases leaf protein levels and nutritional content.Herbivorous insects in elevated CO₂ conditions show a 22 percent decline in abundance, 17 percent increase in consumption rates, 4 percent increase in development time, 9 percent decrease in relative growth rate, and 5 percent decrease in pupa weight.These are average changes that vary by species and are most pronounced for chewing insects.These changes suggest that climate-induced increases in CO₂ levels will likely have

A) uniformly positive effects on terrestrial ecosystems.
B) uniformly negative effects on terrestrial ecosystems.
C) complex effects on ecosystems that vary by species and trophic level.
D) generally positive effects on plants and negative effects on animals.
E) generally positive effects on chewing insects and negative effects on others.