The correct answer to the question is B) Step - down transformer.
EXPLANATION:
In the given question, we have four electrical devices i.e turbine, step-down transformer, step-up transformer and generator.
The function of turbine and generator is to produce electricity by converting mechanical energy into electric energy.
The function of step up transformer is to increase the voltage of the source. The reverse happens in case of step down transformer.
As per the question, we are interested for safety of home.
Normally the voltage from main station is very high. So, we have to decrease it for the safety of home electrical appliances. So, power lines are passed through step down transformer.
Hence, step down transformer can be safe for our home.
