What could cause you to lose your citizenship of a certain country would be if you decided to betray your country for some reason in some way. This could be done in multiple fashions, one being if you're in the army and you give out a top military secret. This cold make you lose citizenship.
C. A university designs a new building to ensure that astronomers will be able to easily observe the night sky
The correct answer is A. There are more rats than people in our town these days.
Explanation
The Black Death was the most devastating pandemic in human history, affecting Europe and parts of Asia during the 14th century. The main reason why this disease spread quickly was due to the increase of rats throughout Europe, because the disease was transmitted by the bite of rat fleas. Therefore, the sentence of the fragment that illustrates the real cause of the plague is A. There are more rats than people in our town these days.
Poland, east germany, and ussr