Practice UPSC CSAT previous year questions from 2011–2026 classified underBlood Relations. Review the original question, four options, correct answer and explanation for every PYQ.
13 questions • 2011–2026
P has a son and a daughter. S is the mother of T. S is R’s spouse. Q and R are children of P. Then how is Q related to S?
Q and R are siblings. S is R's spouse, so Q is the sister of S's husband under the relationship implied by the options. Hence D.
P is the brother of Q and R. S is R’s mother. T is P’s father. How many of the following statements are definitely true? I. S and T are a couple. II. Q is T’s son. III. T is Q’s father. IV. S is P’s mother. V. R is T’s daughter. VI. P is S’s son. Select the correct answer using the code given below:
II, III, IV and VI are definite; I assumes couple status and V assumes R is female.
There are 5 members A, B, C, D, E in a family. What is the relation of E to B? 1. A and B are a married couple. 2. D is the father of C. 3. E is D's son. 4. A and C are sisters. Which option is correct?
All four statements together establish E as B's brother-in-law.
Natural selection cannot anticipate future environments on the earth. Therefore, the set of existing organisms can never be fully prepared for environmental catastrophes that await life. An outcome of this is the extinction of those species which cannot overcome environmental adversity. This failure to survive, in modern terms, can be attributed to the genomes which are unable to withstand geological vagaries or biological mishaps (infections, diseases and so on). In biological evolution on the earth, extinction of species has been a major feature. The earth may presently have up to ten million species, yet more than 90% of species that have ever lived on the earth are now extinct. Once again, the creationist doctrines fail to satisfactorily address why a divine creator will firstly bother to create millions of species and then allow them to perish. The Darwinian explanation for extinct life is once again simple, elegant and at once convincing - organisms go extinct as a function of environmental or biological assaults for which their inheritance deems them ill-equipped. Therefore, the so-called Darwinian theory of evolution is not a theory at all. Evolution happens - this is a fact. The mechanism of evolution (Darwin proposed natural selection) is amply supported by scientific data. Indeed, to date no single zoological, botanical, geological, paleontological, genetic or physical evidence has refuted either of the central two main Darwinian ideas. If religion is not taken into consideration, Darwinian laws are acceptable just like the laws proposed by Copernicus, Galileo, Newton and Einstein - sets of natural laws that explain natural phenomena in the universe.
P, Q, R, S, T and U are six members of a family. R is the spouse of Q. U is the mother of T and S is the daughter of U. P's daughter is T and R's son is P. There are two couples in the family. Which one of the following is correct?
From the relationships, R and Q form one couple; R's son is P, and P's daughter is T. Thus T is the granddaughter of R and Q. The uploaded key marks Q36 as dropped (X), but the relationship question itself has answer D.
A family of two generations consisting of six members P, Q, R, S, T and U has three males and three females. There are two married couples and two unmarried siblings. U is P’s daughter and Q is R’s mother-in-law. T is an unmarried male and S is a male. Which one of the following is correct?
The family constraints can be satisfied with R as U’s husband: Q is R’s mother-in-law through her daughter U, while the remaining sex and marriage conditions can be accommodated with P, S and T. Thus option A is consistent.
Four persons A, B, C and D consisting of two married couples are in a group. Both the women are shorter than their respective husbands. A is the tallest among the four. C is taller than B. D is B’s brother. In this context, which one of the following statements is not correct?
D is B's brother, so C being taller than D is not forced by the given constraints; the other statements are consistent with the family and height relations.
A, B, C, D, E, F are members of a family. They are engineer, stenographer, doctor, draughtsman, lawyer and judge (not in order). A, the engineer is married to the lady stenographer. The judge is married to the lawyer. F, the draughtsman is the son of B and brother of E. C, the lawyer is the daughter-in-law of D. E is the unmarried doctor. D is the grandmother of F. There are two married couples in the family.
What is the profession of B?
From the family constraints, B is the judge, so the answer is A.
A, B, C, D, E, F are members of a family. They are engineer, stenographer, doctor, draughtsman, lawyer and judge (not in order). A, the engineer is married to the lady stenographer. The judge is married to the lawyer. F, the draughtsman is the son of B and brother of E. C, the lawyer is the daughter-in-law of D. E is the unmarried doctor. D is the grandmother of F. There are two married couples in the family.
Which of the following is/are a couple/couples?
The two couples are A-D and B-C, so the answer is C.
A, B, C, D, E, F are members of a family. They are engineer, stenographer, doctor, draughtsman, lawyer and judge (not in order). A, the engineer is married to the lady stenographer. The judge is married to the lawyer. F, the draughtsman is the son of B and brother of E. C, the lawyer is the daughter-in-law of D. E is the unmarried doctor. D is the grandmother of F. There are two married couples in the family.
What is the profession of D?
D is the stenographer, so the answer is B.
Given that: 1. A is the brother of B. 2. C is the father of A. 3. D is the brother of E. 4. E is the daughter of B. Then, the uncle of D is
D is E’s brother and E is B’s daughter, so B is D’s parent. A is B’s brother, making A the uncle of D.
A, B, C, D and E are members of the same family. There are two fathers, two sons, two wives, three males and two females. The teacher was the wife of a lawyer who was the son of a doctor. E is not a male, neither also a wife of a professional. C is the youngest person in the family and D is the eldest. B is a male.
How is D related to E?
The constraints place D as the older male married to E; hence D is E's husband.
A, B, C, D and E are members of the same family. There are two fathers, two sons, two wives, three males and two females. The teacher was the wife of a lawyer who was the son of a doctor. E is not a male, neither also a wife of a professional. C is the youngest person in the family and D is the eldest. B is a male.
Who are the females in the group?
E is explicitly female; resolving the family structure makes A the other female.
A, B, C, D and E are members of the same family. There are two fathers, two sons, two wives, three males and two females. The teacher was the wife of a lawyer who was the son of a doctor. E is not a male, neither also a wife of a professional. C is the youngest person in the family and D is the eldest. B is a male.
Whose wife is the teacher?
The teacher is the wife of the lawyer, and the lawyer is the son of the doctor. The family constraints identify D as the husband whose wife is the teacher.
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