Stewart wants to know how many students in his school enjoy watching sports on TV. He asks this question to all 25 students in his science class and finds that 60% of his classmates enjoy watching sports on TV. He claims that 60% of the school's student population would be expected to enjoy watching sports on TV. Is Stewart making a valid inference about his population?

Yes, it is a valid inference because he asked all 25 students in his science class
Yes, it is a valid inference because his classmates make up a random sample of the students in the school
No, it is not a valid inference because his classmates do not make up a random sample of the students in the school
No, it is not a valid inference because he asked all 25 students in his science class instead of taking a sample from his math class