B, advocate. Being an advocate means you speak out for it, or that you show your support for something.
The research error described above is an example of selection bias.
Selection bias takes place when, from a population of interest, a group of individuals is selected in order to construct a sample but without a proper randomization. The result is a sample which is not representative of the underlying population.
According to the example, the target population of the research comprises all students but the sample only includes boys. Hence, selection has not been random because it followed a gender criteria, and the results obtained using it cannot be applicable to the whole population because they are affected by a selection bias.
Answer: social contract
Explanation: Because Ginny's mother has accompanied her daughter on multiple occasions she has both taught and tested her on the safety rules. Ginny has demonstrated mastery of them and consistency in their application. Consequently, Ginny agrees to follow the rules and in exchange her mother allows to go to the park unaccompanied.
