I was given "Another correct solution: Apple and an," which is missing a word. On this page the solution is listed as "Apple and an/aorange." I cannot report either of these with the canned responses.
Yáʼátʼééh! When the English answer is wrong, please try always to send a report. If it is not possible to report the English solution or a missing word, then try reporting the Navajo sentence so that the contributors will receive a message to fix the exercise. So, they will decide what problem needs to be fixed, no matter what you have marked in the report. :)
There were the two issues that I noted, and only three options to respond. I'm not sure that clicking "My answer should have been accepted," which is not true, would have alerted the mods to what I wanted to say. In fact, I'm sure they would ignore it as an incorrect answer that a confused student thought should have been marked right. Having ridiculously limited canned responses is about the least sensical thing Duolingo could possibly do.
Now having said all that, I did report this sentence by clicking all three options if I remember correctly.