I believe the answer is C) Covariation
The strength of the it is that it reminds all theorists that they are also are a product of what they study and that they should also never forget that. There is never a final objectifying.
whereas, the disadvantage of it is it seems inevitable almost that engaging in such a deep and complex study will have an different effect on the sociologist’s ability to work with the everyday world in a free and uncomplicated manner.
Transportation. Hope this helps. ♥
D) Energy Conservation. Wind power would be one of them