Too simplistic. Based on the generally available reports, and based on prior probabilities given the way this stuff has tended to work all over the world, I tentatively believe something close to this:
There is forced re-education, forced de-radicalization, and forced political (and cultural) assimilation. One major motivation is probably to fight a (largely illusory) danger of widespread separatist violence. In fact, the policy will probably eventually provoke or exacerbate such violence from at least a significant minority. That in turn will confirm in the leader's minds that the entire populace is dangerous, leading to a heavier crackdown. Lather, rinse, repeat.
Some voluntary vocational education is available, not necessarily in "camps", but probably in somewhat less restricted residential settings as well as on an "outpatient" basis. This "education" has a significant political component, which is largely unnoticed by the people who create the curriculum. Failure to absorb the political component is failure to absorb the lessons, and is treated as such.
Some unknown, but probably not very large, number of people accept this on a truly voluntary basis. Another unknown, but probably larger, number accept it "voluntarily", because they expect full-on involuntary internment if they do not. Both of these "voluntary" groups probably do get privileges like the possibility to occasionally get a pass to leave the camp (or other facility). Neither group is probably as large as the outright involuntary group, but it's hard to tell.
Unless you can put on a good show of actually qualifying to "graduate", guitting the "voluntary" group probably has a better than even chance of getting you put into the "involuntary" group. On the other hand, if you're genuinely an enthusiastic member of the "voluntary" group, and you manage to prove it, that's a great thing and you'll get all kinds of rewards.
No genocide is intended; assimilation is intended. The goal is not so much to erase any existing cultural identity as to make it subordinate to "Chinese" identity. That includes accepting a healthy helping of Han, but the people defining the goals don't see that, and think of it as accepting "universal values and pro-social habits". The intended assimilation would have the long-term effect of erasure and might meet the UN definition of "genocide"... but that's not really the purpose.
There is no intentional genocide in the sense of planned mass extermination. Nobody is killed outright unless they resist with violence. They are, of course provoked to so resist, but that's not really intentional. Of course anything that looks like participation in or aid to rebellion counts as violent resistance.
If things escalate enough there may be more dehumanization, and a perceived need for a "final solution", but that's not what the bosses want to do, and they are probably not thinking in those terms at this point.
The intent with regard to religion is to tame it, and those in charge feel they're enlightened and lenient for not outright suppressing it. The "taming" includes bringing the practice under state supervision and control, and removing any doctrinal elements that the regime finds threatening or that might in any way tend to undermine the regime's own doctrines. Some of the altered elements are probably important to the religion as it exists and as it is presently seen by its practitioners. It's very hard to create a recognizable "socialist Islam".
The re-educators, for their part, cannot understand why anybody would be unwilling to accept the "obviously reasonable" changes they're asking for, and see any resistance as vicious intransigence.
The brutality, in or out of the camps, is neither policy nor incidental. It's just what happens when you round people up and tell your troops that they're recalcitrant and anti-social and need to be "re-educated". But Those In Charge are predisposed not to see the brutality as what it is. It's simply tough love for the recalcitrant, with the occasional rare aberration. If a guard manages to make the bosses see something as brutal, that guard is probably punished with extreme severity.
Artefacts, buildings or whatever aren't an issue unless they become rallying points or are seen as likely to be rallying points. However, "not an issue" also includes "not very important to preserve". Which may make them into rallying points.
The goal is to have everybody in the camps re-educated (or brainwashed, as we crazy outsiders would have it), and released. It's a regrettable reality that certain elements resist this reasonable re-education, and therefore must be detained for very long periods, maybe even for life. It wouldn't be appropriate to release anybody who hadn't actually been reformed. After all, it's for their own good, and don't doubt that the people at the top of this believe that it's for their own good. Of course, if somebody resists "criminally" and becomes an enemy of the state, they may be imprisoned, or, justifiably, executed judicially, or killed as imminent threats to the safety of the state, the state's agents, or the social order.
How many people they actually manage to release is hard to tell. Exactly how hard they try, or what they accept as adequate evidence of having been re-educated, is also hard to tell. It probably varies.
It's also a regrettable reality that there are many unregenerate elements in the populace. Whether it gets to a million, I don't know.
So sort of C with elements of A, but it's more complicated than that.
You would think they'd have learned about some of this from the Cultural Revolution, but apparently not.