Solve clearly

Consider the estimated regression Tag-gure = 705 _ 5 u. STran'g, where TestScore indicates the test score and STratio indicates the student teacher ratio (e.g., the number of students per teacher). According to the estimated regression, if the schools hire more teachers and lower the studentteacher ratio by 4 students per teacher. then the test score is expected to Q A. improve by 4. O B. improve by 20. O C. drop by 20. O D. drop by 5