Bheja fry question

 This bheja fry question I read on the Internet recently.

Question 

If Therasa's daughter is my daughter 's mother, what am I to Theresa???

1.  Grandmother

2. Mother 

3. Daughter

4.  Granddaughter 

5. I am Theresa

Answer 

To solve the problem we need to carefully look into the relationships. 

Teresa's daughter is child of Theresa. 

My daughter 's mother refers to the person who is the mother of speaker' s daughter.

If the  " mother of my daughter" is Theresa 's daughter, then it means that person who is asking question is Theresa' s daughter.

So, answer is      daughter.