Actually, only one of these cities would be enough to answer the question, as they both lie only on the sea: the Baltic sea.
The Baltic sea joins the Atlantic Ocean next to Denmark.
The answer is C.
I got this answer by the process of elimination. Not A - Because it is a holy book consisting of the words of God (or Allah) that were revealed to Muhammad in a cave. Not B- The Quran is known for being written in only one language--that's Arabic (translations may be done in different languages, but a Quran itself will always be in the Arabic language.) Not D - Muslims constantly follow the Quran because it is their holy book, much like a Christian with the Bible or a Jew with the Torah.
Hope this helped!
It's the study of how the enviroment predisposes where societies are based.