UGC NET Questions (Paper – 1)

Statements A, B, C and E correctly describe the truth-table method for testing validity, while D is false. Validity depends on what happens in all rows where premises are true: if the conclusion is always true in those rows, the argument form is valid; if there is even one row with true premises and a false conclusion, the form is invalid. We therefore must systematically inspect all such rows, not just one arbitrarily chosen row. In UGC NET, many candidates reason through small tables mentally, illustrating E.

Option A:
Option A is incomplete as it omits E, not acknowledging that mental truth-table reasoning is often used in the exam. A, B, C only therefore does not fully incorporate the exam-oriented aspect of the question.

Option B:
Option B is wrong because it leaves out C, neglecting the explicit description of the counterexample row that makes a form invalid. A, B, E only thus fails to give the full condition for invalidity.

Option C:
Option C is correct since it combines the method for finding rows with true premises, the criteria for validity and invalidity, and the exam practice of mental truth tables while excluding D. It reflects standard teaching and UGC NET expectations.

Option D:
Option D is incorrect because it omits A and claims that inspecting only one arbitrary row is sufficient, which contradicts the requirement to check all rows where premises are true. B, C, E only therefore cannot be correct.