Pointing to a portrait of a lady, Kanika said, “Her daughter-in-lawis the wife of my son’s grandfather’s only son.” How is the lady in the portrait related to Kanika?

Mother-in-law

ATQ,

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Please note:

  l   ⇒ Vertical line shown "generation gap".

 =  ⇒ Double lines shown "relation of spouse" 

—  ⇒ Horizontal line shown "relation in same generation other than spouse".

     ⇒ Rectangular box shown " Male".

     ⇒ Circular box shown " Female".

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