Carla wants to know how many students in her school enjoy watching reality tv shows. she asks all 22 students in her science class and finds that 40% of her classmates enjoy watching reality tv shows. she claims that 40% of the school's student population would be expected to enjoy watching reality tv shows. is carla making a valid inference about her population?

no, it is not a valid inference because her classmates do not make up a random sample of the students in the school

no, it is not a valid inference because she asked all 22 students in her science class instead of taking a sample of the students in her school

yes, it is a valid inference because she asked all 22 students in her science class

yes, it is a valid inference because her classmates make up a random sample of the students in the school