Four people take part in a health survey.
Table
| Person | Used a condom during sex | Tested positive for an STI |
|---|---|---|
| P | yes | no |
| Q | no | no |
| R | yes | yes |
| S | no | yes |
Which statement is supported by the table?
condom use always prevents every sexually transmitted infection
absence of condom use always leads to a sexually transmitted infection
these four results cannot establish how effective condom use is
these four results show that condoms increase the risk of infection
43 exam-style questions on Edexcel GCSE Biology 5.1 Health and communicable disease, covering 5.1.1 Communicable and non-communicable diseases, 5.1.2 Disease susceptibility interactions, 5.1.3 Pathogens as disease-causing organisms, 5.1.4 Common infections, 5.1.5 Spread and prevention of pathogens, 5.1.6 Lifecycle of a virus, and 5.1.7 Spread and prevention of STIs. Each one has a worked solution and a mark scheme showing where the marks go.