Answer:
B. increase the unemployment rate by increasing the opportunity cost of job search
Explanation:
Unemployment is inability of people able & willing to do a job , to get a job. Opportunity Cost is the cost of next best alternative foregone while choosing an alternative.
A Job has an opportunity cost in terms of sacrifised 'unemployment insurance' by government. If the unemployment insurance by government increases, it increases the opportunity cost of job search. This would tend to bring an increase in the unemployment rate.
