Answer:
Correct option is (a)
Step-by-step explanation:
Real income is the income after adjusting for inflation. Inflation is rise in general price of commodities. Here, friend was living in a small town. Cost of living as well as inflation is lower as compared to big city like Washington DC. Even though he is given a raise of $10,000 that is an increase in nominal income, his real income after adjusting inflation and cost of living would not rise by $10,000.
So, friend should not get excited to be moving to the city with higher pay as it will not make much of difference.