Truth functions and logical status – UGC NET Question

Statements D and E are wrong, while A, B, C and F are correct. A and B correctly describe the truth conditions for conjunction and inclusive disjunction, and C accurately symbolises the exclusive “either–or”. F is true because truth tables are standard tools for checking validity. D mistakenly describes a tautology instead of a contradiction, and E wrongly describes the condition for a contingent statement rather than a tautology, so these two are the wrong statements.

Option A:
Option A is incorrect because it singles out only D as wrong and ignores E, which also misrepresents the definition of a tautology. Since both D and E give inverted definitions, treating only one of them as wrong undercounts the errors. Therefore this option does not match the full set of wrong statements.

Option B:
Option B is also incomplete, as it selects only E and ignores D. D is clearly false because a contradiction is never true in any assignment, not always true. By failing to include D, this option again fails to capture all wrong statements listed.

Option C:
Option C is correct because it groups exactly D and E, the two statements that invert the standard meanings of contradiction and tautology. It leaves A, B, C and F untouched, all of which correctly describe truth-functional connectives and the use of truth tables. This combination therefore matches the required set of wrong statements.

Option D:
Option D is wrong because it adds B, which is a correct description of inclusive disjunction, to the set of wrong statements. B rightly states that “p or q” is false only when both p and q are false. Including B beside the genuinely wrong D and E makes the option logically inconsistent.