Colonialism is synonymous with modernization and improvement

On the campaign trail in 2012, President Barack Obama deemphasized his work on __________, in part due to the deep divisions in public opinion on the issue

Fill in the blank with the correct words.

Using already existing groups for research implies that

A) participants cannot be randomly assigned. B) the research project is doomed to fail. C) any comparisons made between the groups are meaningless. D) participants have already been randomly assigned.