How did the black death change the european economy?

The plague had an important effect on the relationship between the lords who owned much of the land in Europe and the peasants who worked for the lords. As people died, it became harder and harder to find people to plow fields, harvest crops, and produce other goods and services. Peasants began to demand higher wages.

answer is b.

  it is always the best policy to have good communication and good relations between individuals and, specially, between leaders of the countries. for this purpose, among others, there is a common place, the united nations, where the representants can present his and learn about the other country's policies.