What caused great britain and france to declare war on germany in 1939?
a) the appeasement policy
b) the invasion of poland
c) the nonaggression pact
d) the surrender of poland

The correct answer is B. What caused Great Britain and France to declare war on Germany in 1939 was the invasion of Poland.

The German invasion of Poland was a military action of Nazi Germany aimed at annexing the Polish territory. The operation began on September 1, 1939 and the last units of the Polish army surrendered on October 6 of that same year. It was the trigger of the Second World War in Europe, as it forced the declaration of war by France and the United Kingdom, and ended with the Second Polish Republic.

from the conditions of the working class in england by friedrich engels,the main idea is :

austria

hugary

yugoslavia

czechoslovakia