‘R8S’ means ‘R is the father of S’.
‘R7S’ means ‘R is the sister of S’.
‘R6S’ means ‘R is the brother of S’.
‘R2S’ means ‘R is the wife of S’.
Which of the following expressions represents ‘X is the mother of Y’?

X2M8Y

After checking all the options, we get the answer from option (iii):

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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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