Hello!
The experiment this question refers to is Pavlov's Dogs.
Ivan Pavlov was a russian physiologist who is most known for his work with classical conditioning.
The Soviet Union had set up official border stations in which you had to cross to get to the other side. Eventually, they had set it up so they're was only one safe way to get to West Berlin, just one border stations. These border stations were quite strict, as they had people trying all sorts of crazy ways to get to West Berlin.
Answer:
B- Gained wealth by buying, selling, and trading for goods in the triangle trade
Explanation