Increasing national income without effective control of population size in a country can lead to

Step 1: Analyze the question The question asks what happens when national income rises but population growth is not controlled. The key idea is the link between national income, population and per capita income.

Step 2: The concept Per capita income = National Income ÷ Population

If population grows as fast as, or faster than, national income, each person's average share does not improve. It may even fall. When average income falls or stagnates, living standards drop and poverty spreads. This is why many developing countries, including Nigeria, can record GDP growth and still see widespread poverty.

Step 3: Work through the options

• A. Higher per capita income: This is wrong. It would only happen if income grew faster than population. Uncontrolled population growth works against it.
• B. Increase in poverty: This is correct. A rapidly growing population shares the national income among more people, so the average share shrinks. There is also more pressure on food, housing, healthcare, education and jobs, and that deepens poverty.
• C. Increased outflow of aid: This is wrong. Population growth does not cause a country to send out more aid. Poorer countries usually receive aid.
• D. Underutilization of resources: This is wrong. A large population usually means more pressure on resources, not unused ones. Underutilization is a different problem, caused by poor management, lack of capital or technology, and similar factors.

Step 4: Answer Suppose national income rises by 3% but population rises by 4%. Per capita income falls by about 1%, so people are worse off on average and poverty increases.

The answer is B. increase in poverty.

Step 5: Exam tip Whenever you see "national income" together with "population", think of per capita income = national income ÷ population. If population outpaces income growth, living standards fall. Economics questions on development and population nearly always come back to this relationship.