A study recorded exposure to air pollution and occupational dust in adults.
| Air pollution exposure | Occupational dust exposure | Adults studied | Adults with lung disease |
|---|---|---|---|
| Low | No | 1200 | 12 |
| Low | Yes | 500 | 15 |
| High | No | 800 | 32 |
| High | Yes | 200 | 20 |
Which statement is supported when the different group sizes are taken into account?
The high-pollution group without dust exposure has the greatest disease percentage, because it has the most affected adults.
The low-pollution group exposed to dust has a higher disease percentage than the high-pollution group without dust exposure.
The high-pollution group exposed to dust has the greatest disease percentage, although another group has more affected adults.
Occupational dust exposure is associated with a higher disease percentage only in the adults with high air-pollution exposure.
102 exam-style questions on Edexcel GCSE Biology 5.4 Non-communicable diseases, covering 5.4.1 Interaction of factors in non-communicable disease, 5.4.2 Lifestyle factors and non-communicable disease, and 5.4.3 Treatments for cardiovascular disease. Each one has a worked solution and a mark scheme showing where the marks go.