Question

In each question below are four statements followed by four conclusions numbered I, II, III and IV. You have to take the four given statements to be true even if they seem to be at variance from commonly known facts and then decide which of the given conclusions logically follows from the four given statements disregarding commonly known facts. Then, decide which of the answers (a),(b),(c),(d) or (e) is the correct answer.

Statements
Some pins are needles.
Some threads are needles.
All needles are nails.
All nails are hammers.

Conclusions
I. Some pins are hammers.
II. Some threads are nails.
III. Some pins are threads.
IV. No pin is a thread.

• A. Only I, II and either III or IV follows
• B. Only I follows
• C. Only either II or III follows
• D. Both III and IV follows
• E. All follow

Answer 1

The correct option is A Only I, II and either III or IV follows

Mediate term of the following are Some pins are needles (I-type)
All needles are nails (A-type)
$I+A\to Itype$
Some pins are nails.
Another mediate term is
Some pins are nails (I-type)
All nails are hammers. (A-type)
$I+A\to Itype$
Some pins are hammers
(Conclusion I follows)
Another mediate term is
Some threads are needles. (I-type)
All needles are nails (A-type)
$I+A\to Itype$
Some threads are nails
(Conclusion II-follows)
Conclusion III or VI are a complementary pair.