Concept:National income is the total income earned by factors of production in a country within a period.
In developing countries, labour is the most abundant factor.
Explanation:Households receive income from wages, salaries, rent, interest, and profit.
The largest share of national income in developing countries comes from compensation to employees.
Most workers are employed in agriculture, trading, and low-skilled services.
Their major earnings are wages and salaries paid for their labour.
Income from rent, interest, and profit is smaller because capital and land ownership are concentrated among few people.
Thus, the largest component of national income is wages and salaries.
Answer:D. wages and salaries