Hey there!
The correct answer that fills in the blank would be "Although".
The reason for this is because of the fact that the sentence is contrasting two ideas. The key word that hints this would be the conjunction "but". The word "although" best fits this sentence as it is a word that helps contrast two ideas in a sentence as compared to the other options.
The answer cannot be "wherefore" as this word is used more to show a cause and effect relationship between two ideas.
The answer cannot be "even" since this word is more used to emphasize an idea which does not appear to be the purpose of the sentence.
The answer cannot be "yet" despite the fact that it also contrasts two ideas. The word "yet" is more used in the situation where the speaker is stating an idea but then they negate it with a contrasting idea (i.e She studies hard yet her grades are atrocious.)
Hope this helps! :)