One antibiotic was used to treat infections in a hospital for five years. The table shows the percentage of the bacteria in the hospital that were resistant to this antibiotic.
Table: The percentage of bacteria in one hospital that were resistant to an antibiotic during five years of use of that antibiotic
| Year | Percentage (%) of bacteria that were resistant |
|---|---|
| 1 | 2 |
| 3 | 15 |
| 5 | 61 |
Which statement explains the change shown in the table?
The antibiotic caused the bacteria in the hospital to mutate more often
Resistant bacteria survived the antibiotic and reproduced, so their number rose
Bacteria that were not resistant became resistant while the antibiotic was used
Patients in the hospital became resistant to the antibiotic over the five years
40 exam-style questions on AQA GCSE Biology 6.3 The development of understanding of genetics and evolution, covering 6.3.1 Theory of evolution, 6.3.2 Speciation, 6.3.3 The understanding of genetics, 6.3.4 Evidence for evolution, 6.3.5 Fossils, 6.3.6 Extinction, and 6.3.7 Resistant bacteria. Each one has a worked solution and a mark scheme showing where the marks go.