Answer:
A. principal interviewed the 25 students who scored highest on a reading test.
D. For a report on the exercise habits of adults, Sergio talked to 30 adults at a local fitness center.
E. Josh asked the first 25 people he met at the dog park if they preferred dogs or cats.
Step-by-step explanation:
Biased means if the selection of every unit does not have an equal chance of being selected in a sample.
The sample is said to be good if choosing the unit is unbiased. The sample is said to be unbiased if the selection of each unit is independent.
Option A is an example of data selected in a biased way because principal chose only those student who scored the highest marks on reading test.
Options B and C are unbiased as here a selection of each number and name of the student has an equal chance of being selected.
Option D is biased because Sergio talked adults at a local fitness center where people go for maintaining their health. So, there is a chance of the selection of fitted adults more than unfitted adults.
Option E is biased because Josh met people at the dog park where dog lovers are more than a cat lover.