Question

Consider the following statements and answer the question.

M, N, O and P are all different individuals.
M is the daughter of N.
N is the son of O.
O is the father of P.

Which among the following statements is contradictory to the above premises?

• A. P is the father of M.
• B. O has three children.
• C. M has one brother.
• D. M is the granddaughter of O.

Hint:

Work out who M's father already is from the given facts, then see which option secretly repeats that role under a different name.

Answer 1

The Correct Option is A

Let's build the family tree first before touching the answer choices. We are told M, N, O and P are four separate individuals. N is the son of O, so N is male and a child of O. O is the father of P, so P is also a child of O, making N and P siblings. M is the daughter of N, so M is N's child, which puts M one generation below N and two generations below O, that is, M is O's granddaughter.

1. P is the father of M: We just fixed M's father as N. If P were also M's father, P and N would have to be one and the same person. But the question already tells us all four, M, N, O and P, are different people, so this cannot happen. This statement clashes with the given facts.
2. O has three children: The premises confirm two of O's children, N and P. They say nothing about whether O has more children or not, so a third child is neither confirmed nor denied.
3. M has one brother: Whether N has other sons or daughters besides M is never mentioned. This statement is an open possibility, not something ruled out by the passage.
4. M is the granddaughter of O: This is precisely what our family tree already shows, since M is N's daughter and N is O's son. This statement matches the premises perfectly.

Out of the four, only the first statement forces two named individuals to secretly be the same person, which the question explicitly does not allow. That makes it the one statement that goes against the given premises.

Let's summarize:

• N and P are both children of O, and M is N's daughter, so M is O's granddaughter.
• Saying P is the father of M would collapse P and N into one person, breaking the "all different individuals" condition.
• The other three statements are either already true from the family tree or simply not addressed by it, so none of them create a contradiction.

So the statement contradictory to the given premises is "P is the father of M".