A school principal wants to know how all students feel about extending lunch by 15 minutes. The principal surveys 200 students who are members of the school’s lunch club. The majority are in favor of a longer lunch. Which statement best evaluates this survey?
The survey is biased because the sample is not representative of all students.
The survey is valid because it only asked students who like lunch.
The survey results mean that all students want a longer lunch.
The survey should only include students who are in class during lunch.
