Most Analysts Focus on the Cost of Tuition as the Way

Most analysts focus on the cost of tuition as the way to measure the cost of a college education.But incidentals,such as textbook costs,are rarely considered.A researcher at Drummand University wishes to estimate the textbook costs of first-year students at Drummand.To do so,she monitored the textbook cost of 250 first-year students and found that their average textbook cost was $600 per semester.Identify the variable of interest to the researcher.

A) The textbook cost of first-year Drummand University students.
B) The year in school of Drummand University students.
C) The age of Drummand University students.
D) The cost of incidental expenses of Drummand University students.