Which of the words pairs has the same relationship
oven : heat
piano : wood
sound : noise
wife : husband

my educated guess would be: Sound: noise

these two words I believe are synonyms therefore making them have the same relationship.  

The others don't have that type of relationship. For example, a relationship to Piano would be maybe keyboard. Hopefully this makes sense and helps.

animal farm, written by george orwell, is a representation of russia after the revolution that led stalin to take over power.

in this excerpt, the central idea seems to be that the animals (a representation of society), when they believe to be working for a greater good and equality, are obedient and productive. they were convinced that, after expelling the owner (jones) from the farm, they would live in harmony and be fairly treated.

as we know, the pigs become the leaders and grow more selfish and dictatorial with time. in the end, they look and act in a way so similar to humans that it is impossible to tell the difference. the ideals of equality are shattered, and the farm turns out to be worse than it was before. the animals are manipulated with false propaganda and forced to work in order to enrich the pigs.