Horse developed a measure of "quality of city life." He included measures of many factors, including: tax rate, quality of school system, cultural and recreational opportunities, pollution, traffic congestion, crime rate, and health care availability for 100 U.S. cities to get a score for each. Dr. Horse created a(n):_____. Choose from the following possible choices the correct answer: (A) scale. (B) statistic. (C) index. (D) measure of central tendency