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A rival researcher believes that the auxin IG3 will be more effective in developing roots than the giberellins were. She obtains five bean plants and treats each one with a different IG3 solution. She then measures the length of the main root every 3 days. Her results are summarized in the table below:

$$ \text{ Length of Main Root (cm):} $$

Plant # Conc. of IG$_3$ (ug/ml) Day 3 Day 6 Day 9 Day 12 Day 15
1 20 2 2.2 2.5 2.8 3.1
2 40 2 2.4 2.6 2.9 3.1
3 60 2 2.1 1.7 1.4 .7
4 80 1. 1.2 .9 0 0
5 100 1.5 .8 .5 0 0

A Scientist decides to test the effect the addition of giberellic acid has on root growth in newly planted pea shoots. She sets up an experiment where she will test various concentrations of giberellic acid solution. She sets up five groups of twenty-five plants each. Four of the groups are watered daily with various concentrations of giberellic acid solution, the fifth with water without any additives. The length of the main root was measured every 3 days in each plant and the average of each group was recorded. The results are summarized in the data table below:

$$ \text{ Length of Main Root (cm):} $$

Plant # Conc. of IG$_3$ (ug/ml) Day 3 Day 6 Day 9 Day 12 Day 15
1 0 2 2.2 2.5 2.8 3.1
2 10 2.1 2.5 2.9 3.3 3.5
3 20 1.9 2.7 3.0 3.5 3.9
4 30 2.2 2.9 3.3 3.7 4.1
5 40 2.0 2.3 2.4 2.4 2.5

The researcher ignores her colleague’s advice and goes ahead with a plan to publish. Her concluding remarks begin with this statement: “Based on the data collected, we see that IG3 is…”

Which statement, based on the data, would work best to finish the conclusion?

A

A concentration of 40ug/ml is most beneficial to root growth in corn plants.

B

High concentrations of IG3 are lethal to root growth as compared to lower concentrations.

C

All concentrations of IG3 can be lethal to root growth in corn plants.

D

Overall, IG3 is a useful molecule to aid in the root growth of plants.