Quick Grammar QUestion

So I was doing Ivy Global, 1e, and this question popped up. I’d appreciate any help I can get!

“We have placed our health in the hands of physicians with the trust that they will act ethically and (thinking about our most important interests).”

A) NO CHANGE
B) with our best interests in our minds
C) in our best interest
D) eks I don’t remember this one but it was 100% wrong.

So basically, I chose B even though it’s a litt;e wordy because it had “interests” instead of “interest” like it is in C. Of course, Ivy G says C is the right answer, but because of the numerous typos I have found, I’m sorta doubting C. Like maybe they meant to put interests instead of interest. And when do you put interest or interests? Thanks!

Terrible question. It has to be © (because (B) says in “our” minds and it should be in “their” minds), but this isn’t at all how parallelism is tested on the SAT.

Just bad.
@lollypip

@marvin100 is right. That’s a terrible question. Don’t trust none official material. Use real CB material.

^^ Trust what they said
but to answer one of your questions: “in ___ best interest” is an idiom. “Interest” singular.

@marvin100 @mmk2015 ooops ok my mistake it’s supposed to be “their minds” I typed it wrong. So which is right now?

@flatKansas thanks for answering my question, but I’m still confused because in other websites, they said interests and interest were both idioms.

Whether B says in our minds or in their minds, these last words aren’t necessary. C is best.

@CheddarcheeseMN so the interests v interest doesn’t matter?

It’s not clear if it should be interests or interest. http://ell.stackexchange.com/questions/43225/its-im-acting-in-your-best-interest-interests. B sounds more direct – why add “in their minds” if it isn’t needed?

Thanks. So in terms of interest/interests, there is no direct answer?

Choice C is best, but as for interest/interests, I vote this way:

I can keep your interests in mind or your best interest.

(Although I guess that among your interests, several could be tied for best, but I don’t think the idiom considers that possibility…I also don’t think a real SAT question would hinge on this.)

@pckeller I still don’t get it, but if the real SAT doesn’t hinge on stuff like this I’ll just ignore it and move on. Thanks!

Yeah, I am probably not right anyway. As a math guy, I tend to over-try to make grammar something that follows logical rules with mathematical precision. Sometimes it works, other times not so much. Here I was thinking that I could be watching out for your best interests, a plural because you can have several interests and I could be watching out for all of them. But if one of those is your best interest, singular, then I can keep your best interest, singular, in mind. Still, let it go unless you see it on a college-board test.