Refer to the Table Below

Multiple Choice

Refer to the table below. A biologist studied plant growth using two plant species grown over a 2-week period.For each species, 20 plants were used, randomly split into control and experimental groups.Except for CO₂ exposure, conditions were identical for all plants.The table summarizes results as average height increase, along with a plus/minus value indicating the range of individual plant heights measured.Which is the null hypothesis that would be developed when using statistics to analyze these results?

A) The growth rates of certain species of plants are more influenced by CO₂ levels than others.
B) Differences in growth rate at the different CO₂ levels could be due to random variations in the samples of both species.
C) All plants show variation in growth rate when environmental variables are changed.
D) Carbon dioxide is one of many variables that can influence plant growth rate.
E) The effect of CO₂ on plant growth rate depends on the species of plant being investigated.