Explanation:

- Years of schooling: This measures the amount of formal education a person has completed. It directly indicates education level.

- Life expectancy: This measures the average number of years a person is expected to live. While it reflects quality of life and health, it doesn't directly measure education level.

- Teacher-pupil ratio: This refers to the number of teachers relative to the number of students. It influences the quality of education and indirectly relates to education level.

- Enrollment rate: This measures the percentage of eligible students enrolled in school. It directly relates to access to and participation in education.

Correct Answer: Option 2 - Life expectancy is not directly an indicator of education level.