Context: After two years of this , Leigh did not come back . I do not know what became of her . Not a year goes by that I do not think of Leigh and regret the cruelty meted out to her by immature kids who were insensitive , who accorded her no dignity , and whose unkindness must have been a daily trauma for her . I was troubled then by what was done to her , and yet I was a silent member of the same pack .

Question: What may be the reason I feel so guilty ?
Options:
0. I kept playing pranks on her .
1. I did n't stop the abuse if the other kids .
2. I hit her with my car .
3. I broke up with her .
Answer: 1