Concept:Median is the middle value when numbers are arranged in order. For an even count, median is the average of the two middle numbers.Explanation:Arrange the numbers in ascending order: 7, 8, 9, 10, 11, 12.There are 6 numbers (even). The two middle numbers are the 3rd and 4th: 9 and 10.Median = average of 9 and 10 = (9+10)/2=19/2=9.5.Answer:Option D: 9.5