B. 118 feet
To find the median of the data, we first need to arrange the heights in ascending order:
10, 10, 10, 10, 11, 11, 11, 11, 11, 11, 11, 11, 12, 12, 12, 12, 13, 13, 14, 14
There are 20 data points, so the median will be the average of the 10th and 11th values in the ordered list:
(11 + 11) / 2 = 11
So, the median height of the trees is 118 feet.