Final answer:
The statement about adolescents and parental smoking behavior is an example of a hypothesis, a tentative explanation for an observation that can be tested.
Step-by-step explanation:
The statement "Adolescents are more likely to start smoking if one or both of their parents smoke" is an example of a hypothesis. A hypothesis is a tentative statement that proposes a possible explanation to some phenomenon or event. It can be tested through research and experimentation to determine whether it is supported or not by evidence. In research methodology, a hypothesis serves as a starting point for an investigation. If the researcher set out to test this statement, they would be in the phase of developing a hypothesis, which they would then investigate through either observational studies or controlled experiments to gather data that would confirm or refute the proposed relationship between parental smoking behavior and the likelihood of adolescents starting to smoke.