Assuming that you had to choose between:
- They use difference sources of evidence.
- They make different conclusions.
- They are being presented to different audiences.
- They address different topics.
The answer is: They use different sources of evidence (1).
Although both speakers reach the same conclusion on a similar topic, their angle is different and they base their argument on different data. Speaker 1 refers to "recent polls" about city residents' willingness to ride a bike to work depending on the feeling of safety, whereas Speaker 2 quotes a "study by the mayor's office" about car pollution.