Final answer:
The Tuskegee Syphilis Study was highly unethical because participants were not informed about the purpose of the study, were not given proper medical treatment, and could not withdraw from the study. However, they were compensated with free medical care, meals, and burial insurance, making the lack of compensation the incorrect option.
Step-by-step explanation:
The Tuskegee Syphilis Study of 1932 is considered highly unethical for several reasons. First, the participants were not informed about the purpose of the study, as they were told they had "bad blood" instead of being informed about their actual diagnosis of syphilis. Second, they were not given proper medical treatment; even when penicillin became the recognized treatment for syphilis in 1947, the participants were still not administered the antibiotic. Third, the participants were not given the option to withdraw from the study, effectively removing their autonomy and ability to seek treatment elsewhere. However, the statement that the participants were not compensated for their participation is not accurate. In exchange for partaking in the experiment, the men were offered free medical care, meals, and burial insurance. This level of compensation does not mitigate the study's unethical nature, especially considering the deception and harms caused, but it does mean that option 4 is the correct answer to the question about which aspect was not a reason the study was considered unethical.