Answer:This would be an example ofa. snowball sampling
Explanation:
A participant chooses someone else to participate on their behalf in a study or test. This happens in cases where it is not easy to fin the actual potential participants. It is called a snowball because when you roll a ball in an snpw it keeps attaching more snow until it gets bigger. The sampling is done randomly which means it is a non probability sampling
Snowball sampling consists of two steps:
The researcher will choose potential participants which are only few at the beginning. The chosen participants will recruits more participants, they don't have to give names. This recruitment goes on until the desired sample proportion is reached. The participants will only encourage others to come but that is not forced. It can be ethically challenging because subjects can be of sensitive topics
Why is Snowball Sampling Used?
In cases where a research deals with sensitive topics such as cheating, shoplifting, drug use and other deviant societal behaviours, participants may not feel comfortable to come forward. However they may suggest others in similar situation as them and be assured of confidentiality.