As per square of opposition which of the following propositions are so related…
2023
As per square of opposition which of the following propositions are so related that if one of them is true, the other must be false and vice-versa ?
(A) All mammals are vertebrates.
(B) No mammals are vertebrates.
(C) Some non mammals are not vertebrates.
(D) Some mammals are not vertebrates.
Choose the correct answer from the options given below :
- A.
(A) and (D) Only
- B.
(A) and (C) Only
- C.
(A) and (B) Only
- D.
(C) and (D) Only
Attempted by 8 students.
Show answer & explanation
Correct answer: A
The question asks for propositions that are contradictories in the Square of Opposition. Contradictory propositions always have opposite truth values; if one is true, the other must be false. Proposition (A) 'All mammals are vertebrates' is a Universal Affirmative (A-type). Proposition (D) 'Some mammals are not vertebrates' is a Particular Negative (O-type). In the Square of Opposition, A and O propositions are contradictories. Therefore, if (A) is true, (D) must be false, and vice versa.