Sounds like you're torn between selflessness and selfishness. But it's not that simple.
Don't worry about people stealing an idea. If it's original, you will have to ram it down their throats. - Howard Aiken
I know you're not worried about theft, but the second part of the quote is still applicable.
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Adoption requires much more than minimal price. For a start, price is only part of the cost of adoption. Other costs are changes in user behaviour, changes in infrastructure etc. Before you get to that point, users have to know about the new approach and the wonderful claims you have for it; they'll need some kind of assurance that the claims are true; it needs to be in a form where they can easily try it out to assess it (easy-to-adopt). It also needs to be usable.
All of this is a lot of hard work, which is a different kind of fun and excitement from a technology that will change the world. Commercialization is long and difficult - consider how long the mouse/desktop took. It's also a (surprisingly) huge, huge leap from "it works!" to "usable by mortals".
All the above is entirely about your first option "A) release it as open-source for maximum impact", because open-sourcing it does not guarantee in any way that it will have maximum impact - or indeed any impact whatsoever. Of course, you can dedicate your life to promoting it as open source, and make enough money to live on by consulting around it; but IHMO that's not the way to change the world.
It's partly because you won't have the resources for the enormous amount of work involved; it's partly that you won't be rewarded for that work. But it's mostly that your interests are not aligned with changing the world: you'll likely end up with a tool that clever developers can use; and not one that can be deployed easily and quickly by anyone. It will rely on service (provided by said developers, or yourself) rather than as a product.
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To answer your question: the reality of tech adoption is tech improvement. So your job - what you work on day to day - will primarily be about adaption, not adoption. Finding out what people need in the technology, and adapting to that. Providing extra tools that people need to compliment it. Fixing bugs. Making improvements. Discovering fundamental technical problems you hadn't imagined and solving/working around them (adapting to reality.)
What many people seem to do is to try to sell it (C) - if the tech really can stand alone, and there's a clear felt specific existing need for it, then this is viable. Historically, this usually doesn't work (eg. Pagerank wasn't, Xerography wasn't) But can work, eg Birdseye (frozen food - though I think he had an initial business going at that point.)
Many high technology ideas are often sold as (B), but they often involve huge amounts of consultation with the initial customers, while the bugs are sorted out, and especially as you learn what the problem really is. Accounting for this work, the profit margin is negligible (or negative.) As the bugs get worked out, you can start to sell it cheaper.
But if it really is trivial to instantly adopt, without any adaption needed by the user, or by the technology, or by the market, and your claims are self-evident and will be instantly spread... then any of the three options are viable, and it would just be up to you.
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Summary: the answer (IMHO) depends on how much ongoing work is involved in making the product useful and usable by real people: maximizing adaption, not adoption.