The following prompts require explanatory thesis statements because they are asking the writer to compare two things without taking a particular stance on whether one is better or worse.
Make sure to use comparison and contrast phrases to cue the reader to the ways in which you are analyzing the relationship between the subjects. For each body paragraph, you support the thesis by writing about each topic at the same time.
Compare the merits of the two. A possible thesis could be: Though their fates are quite different, both Lily Bart and Judy Trenor willingly seek lives in gilded cages.
Or maybe your supervisor will ask you to write a business proposal recommending one of two different approaches to a project. London has a much richer past than Washington, DC, and consequently has a lot more material to pull from when arranging its collections.
And remember—the thesis is only as strong as the evidence that supports it, so choosing your method before you start writing is a good idea.