Answer:
(C) Elizabeth wants to estimate the mean height of students at her school. She collects data by selecting a random group of students within her classroom.
Explanation:
In option C, the sample is an example of convenience sampling, It is not representative of the population of student being studied.
Convenience sampling is a type of non-probability sampling method in which the sample is taken from the part of the population easy to reach.
The sample are not chosen at random thereby undermining the ability to generalize the results from the sample to the entire population under study.