Hypothetical and disjunctive syllogisms – UGC NET Question

Statements A, B, C, D and F give a correct account of hypothetical and disjunctive syllogisms, whereas E is false. Hypothetical syllogisms use conditionals, and a pure hypothetical form like “If p then q; if q then r; therefore if p then r” is valid. Disjunctive syllogism, “p or q; not p; therefore q”, is a standard valid pattern, and chains of conditionals can be understood as repeated applications of modus ponens. UGC NET questions sometimes hide these structures in ordinary language. E is wrong because the mere presence of “or” does not make an argument invalid; it depends on how the disjunction is used.

Option A:
Option A is incomplete as it omits F, failing to mention that such patterns often appear implicitly in exam questions. While A, B, C and D are true descriptions of the logical forms, they do not connect these forms to their test usage. Thus A, B, C and D only is not fully adequate.

Option B:
Option B is incorrect because it includes E, which claims that all disjunctive syllogisms are invalid, contrary to basic logic where disjunctive syllogism is a paradigmatic valid form. Including E invalidates the entire combination. Hence A, B, C, D and E only cannot be accepted.

Option C:
Option C is wrong as it omits A and includes only B, C, D and F, leaving out the general characterisation of hypothetical syllogisms as involving conditionals. Without A, the picture of the pattern is incomplete. Therefore B, C, D and F only cannot be the right answer.

Option D:
Option D is correct because it gathers all the true statements and excludes E, which mischaracterises the status of disjunctive syllogisms. It accurately reflects the formal patterns and acknowledges how they are embedded in UGC NET reasoning questions. Consequently, A, B, C, D and F only is the appropriate answer.