Why don't you just tell me who is who?
In a small village there are 4 families. Interestingly, each family has a pair of twin sisters. Let the elder sisters be \(ABCD\) and the younger sisters be \(abcd\). One day, you went to the village and saw 8 of them and asked, "Which family are each of you belong?"
\(A\) says, "\(B\) and \(a\) are not twin sisters."
\(B\) says, "\(C\) and \(d\) are twin sisters. "
\(C\) says, "\(D\) and \(c\) are not twin sisters."
\(D\) says, "Among \(ABC\), only the elder sister of \(d\) is telling the truth."
Given that \(D\) is telling the truth, can you know which two are a pair?