Context: Hiding behind the walls of Manji 's sarcastic stoicism never seemed to work for her anyway - she might have known better by now . Emotion dogged her heels , pursuing her almost faster than she could walk . In a rocky , fast - running spot Rin weighted Manji 's kosode with stones to let the water flow through it , sat on the bank nearby while cleaning out her shoulder bag and wept for an infant ghost until her eyes burned .

Question: Why would Rin weight Manji 's kosode with rocks in the fast moving stream ?
Options:
0. Because rocks will make the kosode float under water and clean it well .
1. Because rocks will make the kosode sink and prevent the cleaning .
2. Because rocks will make the kosode sink under water and clean it well .
3. None of the above choices .
Answer: 2