If J is the sister of K. K is the sister of L. L is the sister of M. M is the brother of N. Then which of the following statements is not necessarily true?
(A) K and L are sisters.
(B) M and N are brothers.
(C) L is sister of N.
(D) J, K, L are females and M is male.
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (B) only
The word “sister” or “brother” tells the gender of the person it describes, not of the other person in the pair.
J, K and L are each called a sister, so they are female. M is called a brother, so he is male.
J–K, K–L, L–M and M–N are each brothers and sisters, so all five are children of the same parents.
N’s gender is never given: N is only the one M is a brother of.
(A) K and L are sisters. Necessarily true (Incorrect). K and L are both female and are siblings.
(B) M and N are brothers. Not necessarily true (Correct). M is male, but N may be a brother or a sister.
(C) L is sister of N. Necessarily true (Incorrect). L is female, and N is a sibling of M and so of L.
(D) J, K, L are females and M is male. Necessarily true (Incorrect). Each of them is described as a sister or a brother.