Answer:
The answer is "Option C".
Explanation:
This study looks after results including such illness growth during the trial time, and this includes additional elements such as suspected risk or source of protection (s). The study usually consists of taking and looking at such a cohort of subjects for a long time. The main advantage of these studies is knowledge accumulation and higher efficiency. Systematic reviews may suffer from choice distortion, in addition to the potential indication misinterpretation.