To determine the relationship between Arun and the girl, let's break down the statement: "This girl is the wife of the grandson of my mother." Here's the step-by-step reasoning:
- Start with Arun's mother. If we assume Arun's mother's grandson, then the grandson is Arun's son.
- The statement elaborates that the girl is the "wife of the grandson." Therefore, this girl is the wife of Arun's son.
- When someone is the wife of your son, their relationship to you is daughter-in-law.
- Thus, Arun's relation to the girl is her father-in-law.
Therefore, Arun is the father-in-law to the girl.