The number of vehicles passing through a bank drive-up line during each 15-minute period was recorded. The results are shown below. Find the median number of vehicles going through the line in a 15-minute period. 25 27 25 28 28 25 30 27 35 31 29 24 31 25 20 15 27 27 27 O A. 28 vehicles O B. 27 vehicles O C. 31 vehicles O D. 26.85 vehicles