The following appeared in the summary of a study on headaches suffered by the residents of Mentia.

"Salicylates are members of the same chemical family as aspirin, a medicine used to treat headaches. Although many foods are naturally rich in salicylates, for the past several decades, food-processing companies have also been adding salicylates to foods as preservatives. This rise in the commercial use of salicylates has been found to correlate with a steady decline in the average number of headaches reported by participants in our twenty-year study. Recently, food-processing companies have found that salicylates can also be used as flavor additives for foods. With this new use for salicylates, we can expect a continued steady decline in the number of headaches suffered by the average citizen of Mentia."

Write a response in which you discuss what specific evidence is needed to evaluate the argument and explain how the evidence would weaken or strengthen the argument.