"It can also happen to us."
Translation:Può succedere anche a noi.
Well, "ci" is clitic so the pronoun is kind of "hidden", and it becomes impossible to modify it with an adjective or an adverb. The problem in this case is that "also" doesn't really have to be close to what it refers, so it's hard to tell if the conveyed meaning is that "it can happen too" or "to us too"; but I'd say it's the latter, and duolingo seems to agree. "Anche a noi" means "to us too", while "it can happen too" would make the sentence "può anche succederci", which seems odd out of context.
Well, to quote the Collins a clitic is a word "incapable of being stressed" (http://www.collinsdictionary.com/dictionary/english/clitic); "ci può" is pronounced like "cipuò", i.e. there is no way to stress the "us" part. That's why you need the extended form for it :)
"Anche ci può" is an uncommon word order, but not unused (although judging by a quick online search mostly brought in by the rhetorical "ma anche" that a certain political figure abundantly used): the stress is on the "a" and on the "ò". It brings into focus the "anche" part.
I asked this question 2 years ago. Since then, I have learned the that the correct order is to put the adverb after the verb. I believe when it is at the beginning of the sentence, it changes the meaning to "even", not "also" ("it can even happen"...or at least I think that is correct). If it were before "a noi", it would put the stress on "noi" and mean "even to us". Also, a very useful phrase I've learned since then is "Anche se" (lit: "even if", which we might also translate as "even though").
I tried this as well: anche può succedere a noi. The suggested correction was: può pure succedere a noi, and then here in the comments section the "correct" one is: può succedere anche a noi. It seems to me that they all say the same thing, is that right? Maybe each one stresses different parts and I just don't have a feel for it.