The graph shows the location of Derek's, Evan's, and Frank's houses. Each unit on the graph represents 1 block.
If Frank walks from his house to Derek's house, then on to Evan's house along the path shown, how far will he have walked in blocks? Round your answer to the nearest hundredth.
A) 16.00 blocks
B) 11.31 blocks
C) 19.31 blocks
D) 64.01 blocks