Question

Who always speaks the truth?

• A. A
• B. B
• C. C
• D. D
• A. Father
• B. Mother
• C. Wife
• D. Husband
• A. A’s grandmother alternates between the truth and lie.
• B. C’s wife always speaks the truth.
• C. A’s grandfather always speaks the truth.
• D. B’s daughter always tells lies.

Answer 1

The Correct Option is D

To determine who always speaks the truth, let's analyze the statements made by each family member according to the relationships described:

1. A's Statement: A claims that B is A's son and D is A's mother.
2. B's Statement: B claims that C is B's wife and D is B's father.
3. C's Statement: C claims that D is C's mother-in-law and A is C's daughter.
4. D's Statement: D claims that A is D's granddaughter and B is D's daughter-in-law.

Using logical deductions from these statements:

• From D's statement that A is her granddaughter, A is confirmed to be the child of B and C.
• Since D mentions B as her daughter-in-law, it confirms that C is the son of D, making B's and D's statements compatible.
• However, since B refers to D as his father, B's statement conflicts with D's statement.
• Since B's statement conflicts with D's and A's statement which considers D as her mother, this aligns with C and D's truth assertions.
• Ultimately, as D's statements align with C's assertions and corrects the discrepancies, we conclude:

D is the only member whose statements are logically consistent, making her the one who always speaks the truth.

Answer 2

The question involves understanding the relationships in a family based on given statements: A, B, C, and D are the family members with one couple among them. To deduce B's relation to C, let's analyze each statement: 

1. A: "B is my son. D is my mother."
   This indicates A is B's parent, and D is A's parent.
2. B: "C is my wife. D is my father."
   B is married to C, and D is B's father.
3. C: "D is my mother-in-law. A is my daughter."
   D is C's mother-in-law through B, and A is C's daughter, hence C is A's mother.
4. D: "A is my granddaughter. B is my daughter-in-law."
   A being D's granddaughter, confirms A is B and C's child. B being D's daughter-in-law affirms B is married to her son, C.

From these analyses, B is female and C's wife. Therefore, B is related to C as his wife.

Answer 3

To solve the problem, analyze the given statements and relationships in the family:

• A claims B is A's son and D is A's mother.
• B claims C is B's wife and D is B's father.
• C claims D is C's mother-in-law and A is C's daughter.
• D claims A is D's grand-daughter and B is D's daughter-in-law.

Based on these statements, consider:

1. A says D is A's mother, but D says A is D's grand-daughter. Thus, D could rather be A's grandmother if B is A's parent.
2. B says D is D's father, but it contradicts other statements and implies D would not have a daughter-in-law, hence B is incorrect.
3. C claims D is mother-in-law, indicating C is married to A or B. If C were B’s wife, A would be C's daughter—contradicting since A says D is her mother.
4. D confirms A is grand-daughter and B as daughter-in-law aligns if B is married to the son of D, meaning B’s spouse is C, and C is the son.

Now, evaluate the possible truth:

• A's truth depends on D being the grandmother.
• B is incorrect.
• C states D as mother-in-law aligns if B is C's spouse.
• D's logic holds true if A is the granddaughter and B’s spouse must tell lies.

Considering these observations, the only statement consistent with the contradictions in others is that B’s daughter (C's offspring or A) always tells lies. Therefore:

B’s daughter always tells lies.