You are conducting a study on the health of people who have been exposed to radiation and those who have not been exposed to radiation. which of these methods of obtaining data should you most likely adopt and why?

An observational study

Step-by-step explanation:

When an observational study is done, the individuals are observed but there aren't any attempts to modify their conduct or to manipulate a variable.  There is no treatment given but the simply observation of the subjects who are selected because of certain characteristics.

In this case, an observational study should be helpful because the people have already a pre-existing condition of being exposed to radiation and therefore, the effects on their health can be studied without any new treatments or scenarios.