1. D because "for" serves no purpose in that sentence. You can remove it and still understand the entire message. 2. A, either of your corrections would work, I believe (as a side note, you would say "replace it with" or "change it to", not "replace it to," as you used...just a small correction to help!) 3. C because you don't need to refer to them again as "they." You wouldn't say "Daniel, that American guy, he is smart and charming" you would omit the "he" and just say "Daniel, that American guy, is smart and charming."

"Stands to" could be replaced with "will likely," meaning the same thing.

These are interchangeable as far as I understand.

That sounds like that could be it. But what kind of program are we talking about? That may change the meaning here. From the context "..can succeed in an independent, long-distance environment...", I would gather that, yes, it is referring to a job/program for somewhere with low population.

Well the reference to the window seems unique. I would assume that means that the wood around the window has expanded ( due to maybe temperature or humidity), causing it to keep the window from opening. When I think of something being swollen shut, I think of someone getting a black eye. Say someone got hit hard enough, or enough times, the skin around their eye would swell/expand so much that it would be "swollen shut."

He is insinuating that she isn't very smart, so her teachers/parents should have held her back a grade in school. When you perform poorly in school throughout the year, they will "hold you back" for that grade and make you repeat it(in theory).

Meaning "when they can't afford not to shop sustainably." People will continue shopping frivolously until those actions have pushed them to HAVE to shop sustainably. I'm trying to put this into easier terms to understand. Think of it like this: you may want to go out to a nice restaurant every meal every day, but it wouldn't be very sustainable. Meaning, you couldn't continue that for very long because you would likely run out of money. But, if you insisted on doing so, you'd eventually run out of money, so you would only start eating sustainably until you couldn't afford NOT to eat sustainably. Does this help?

From an American here, technically it should be "media say" but very often I hear (or even say myself) "media says."