Find the odd one out. Justify your answer.
1. GNP, NNP, CSO, GDP
2. Salary, bonus, GPF, free housing, saving
3. Smuggling, production of wheat, sale of second-hand goods, services of housewives
4. Services of teacher, services of engineer, services of lawyer, services of housewife
5. Unemployment allowances, scholarships, old age pension, support price.