I am pretty sure the answer is B
Even though the map wasn't provided, it is possible to answer the question by saying that the correct alternative is letter<em> A: Nazi leaders wanted to keep the existence of extermination camps secret.</em>
The extermination camps were built to murder sistematically jewish, communist and all other kinds of people that the Nazi considered inferior. The idea was to have them in hidden places so as not to cause commotion.
Wires and wooden logs.
Both of these materials were essential for building a strong fortified line during the First World War. Having both of these meant that much more people on one side would survive as it was extremely hard to cross either of the two materials.
