Which survey is most likely affected by bias?

O

a survey of teenagers about their favorite colors

survey of students about vacation policies in a school district

a survey of supermarket shoppers about products they would like to see added

a survey of bike riders on whether they wear helmets

(b) survey of students about vacation policies in a school district

Step-by-step explanation:

The survey is said to be bias if each type of unit is not selected in the sample.

(a) Survey of teenagers is not affected by bias because they were surveying about the teenagers and also take survey from teenagers.

(b) Since they are doing the survey of students but take survey from school district, So result will not equally likely as the opinion of student is different from School district. Thus, this survey is affected by bias.

Same criteria is taken for other two options and they are not affected by bias.