Translation:My professor knows all exhibitions.
The English translation seems to be a bit odd. My professor knows "about" all the exhibitions -would hit the hear much better than "My professor knows all exhibitions." But I get the direct translation!
In German, in Professor(in) reserved for university professors or does it also apply to teachers in general (like in French for example)? Thanks in advance.
In this example I take it that "kennen" is used because it applies to something that the Professorin knows personally (i.e. She has visited many of the Ausstellungen), and not something which she has read about often? (which might use "wissen")
If you can call lecturer a university professor, yes. German is pretty strict, Professor is only a university professor.
Like studieren is to study at university.
One looks at the the exhibitions one by one and asserts that each and every exhibition is known.
One looks at all the exhibitions as a collection or group and asserts that all of them are known.
More a matter of emphasis than meaning, perhaps.
And partly a matter of usage; in English, "everyone" is very common when talking about people but in German, alle is more frequent than jeder -- for example, Everyone is waiting for their food would be more often Alle warten auf ihr Essen than Jeder wartet auf sein Essen.
When I click on the word "kennt" and it shows me available translations, why does it count my answer wrong when I choose the second translation because it's more appropriate according to English grammar?
Difficult to say without knowing what exactly your entire answer was.
But the hints are a bit like dictionary definitions -- not all of them may apply to the current sentence.
For example, in a hypothetical "English for English speakers" course, "lie" might have the hints "be horizontal" and "tell an untruth". Then "Don't lie to me!" can't be translated as "Don't be horizontal to me!" -- regardless of the fact that "lie" can sometimes mean "be horizontal".
What was your entire answer?
I understand your example. I don't remember precisely the translation options that were shown, but they were not as disparate as that. It was more like choosing between "I understand what you mean" and "I comprehend what you mean" and having "comprehend" marked wrong. The correction seemed wrong.