UGC NET Questions (Paper – 1)

Statements A, B, C and E correctly explain how truth tables are used to test validity, while D and F are false. Validity is checked by looking for a counterexample row with true premises and false conclusion, and the absence of such a row shows validity. The number of rows indeed increases exponentially with the number of distinct simple propositions. D is wrong because truth tables work for any finite number of premises, and F is unrealistic about exam expectations, where simpler reasoning is usually sufficient.

Option A:
Option A is incomplete because it omits E, failing to mention the key fact that truth table size grows rapidly with the number of propositions. While A, B and C correctly describe the validity test, they do not fully address the structure of truth tables. Hence this option does not contain all the correct statements.

Option B:
Option B is correct since it brings together the procedural rules for testing validity and the structural observation about row growth, without adding the unrealistic or incorrect claims of D and F. It captures both conceptual understanding and practical awareness. Therefore this option is consistent with how truth tables are taught for UGC NET.

Option C:
Option C is wrong because it includes F, implying that students must always construct very large tables during the exam, which is not expected at Paper 1 level. It also omits C’s explicit statement of the condition for validity. This combination therefore misrepresents both difficulty and method.

Option D:
Option D is incorrect as it includes F and omits A, losing the basic explanation of how truth tables identify invalidity. With F present, it misleads students about exam requirements, and the absence of A leaves out the essential test for counterexamples. Thus B, C, E and F only cannot be the right answer.