Statements : All aeroplanes are trains. Some trains are chairs. Conclusions : I. Some aeroplanes are chairs. II. Some chairs are aeroplanes. III. Some chairs are trains. IV. Some trains are aeroplanes.

Answer: Option D

Since the middle term 'trains' is not distributed even once in the/premises, no definite conclusion follows. However, III is the converse of the second premise while IV is the converse of the first premise. So, both of them hold.