it's letter A. Between 13 and 14 meters
Because one side measure 14, and the height (depth) could not be
higher than 14 meters .
The length of the pond can be calculated using the Pythagorean theorem
length^2 = 36^2 + 14^2
length^2 = 1296 + 196
length^2 = 1492
length = 38.6 m