A medical researcher has applied for funding to continue her experimental treatment for cancer. In her proposal, she lays out several lines of reasoning to persuade both government and private sources to invest in her procedure.
First, she says that her early testing on mice and primates show promising results in reversing cancerous growths.
Second, she says that her previous lab results using show an eradication of cultured cancer cells outside of living organisms.
Third, she says that indigenous people of South America have for hundreds of years used the plant from which her treatment is derived to treat illness.
Finally, she says that the treatment is used in conjunction with an established medical procedure that has been shown to successfully treat Type 1 diabetes, and much of the necessary equipment is available, meaning funds can be used primarily for personnel, lab time, and patient care.
Of the following, which additional argument most strengthens the researcher’s proposal?