Pratima departs from her house and walks 29 m towards the north and then turns right and walks 16 m. Now she turns right again and walks 17 m. She again takes a right turn and stops after walking for 21 m. What is the shortest distance between Pratima and her house now? (Assuming that all turns are 90 degree turns only)

A

17 m

B

18 m

C

13 m

D

12 m