Student "Help" Site Pilfered My Exam Question

Dear Rich: I'm a college professor in the sciences, and over the years I've written a number of questions to assign to students in my various classes. Some of them I'll re-use in subsequent years. Last night I stumbled across one via Google on a site called chegg.com, a site that exists in part to provide answers to students posting questions. When I contacted them asking them to take down that question, the rep I spoke with conferred with others there and told me that they couldn't, and that the situation was effectively no different than if a student had posted a question directly from a textbook. Despite their poisoning of the learning process, I'm not interested in punishing the site, I just don't want to facilitate any future students taking the easy way out and not learning as much as they could. What options (if any) do I have here? Personally I can just scramble a few facts whenever I re-use a question, but I'm curious about the larger ramifications as this sort of student "help" site proliferates online. I would think that this is a question of copyright violation and that if a major publisher with more legal clout than I were to push, the response would be different. Chegg.com, according to its website, is "all about removing the obstacles that stand in the way of the education YOU want and deserve." We assume one of those obstacles is doing homework and that's why the company -- whose primary business appears to be buying and selling textbooks -- offers homework help (advertised to get you better grades and help you "get ready for the real world"). How true!
What they said. We're confused why the rep -- comparing your situation to a student posting a question from a book -- concluded that there was no reason to remove your question. It's true that many questions don't rise to the level of copyright protection because they're too short or because there are a limited number of ways to express the question (the merger doctrine) -- for example, "What are the primary themes in Jacobean literature?" or "What motivated Dwight Eisenhower to run for president?" But we see no reason why a longer question with sufficient detail -- for example, a bar exam hypothetical -- could not be protected under copyright. This would be true regardless of whether the question was pilfered from you, or written for a textbook.
Your challenge is twofold. You face two hurdles: (1) convincing Chegg that your question can be protected by copyright law (see above); and (2) getting Chegg to remove your question. You may be able to accomplish the latter through a DMCA notice via Chegg's IPR program. After all, according to Chegg's website, "if a professor reviews your notes and reports to Chegg that the notes do, in fact, violate their copyright, Chegg will remove the notes." If Chegg doesn't facilitate the removal, we assume you will find it cheaper to modify your questions than to hire a lawyer and threaten a lawsuit.