Question

In each group of questions, below are four statements followed by two conclusions numbered I and II. 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 statements disregarding commonly known facts.

Statements
Some rivers are mountains.
All mountains are plateaus.
No plateau is a sea.
Some seas are rivers.

Conclusions
I. No mountain is a sea.
II. Some seas are mountains.

• A. Only conclusion I follows
• B. Only conclusion II follows
• C. Either conclusion I or II follows
• D. Neither conclusion I nor II follows
• E. Both conclusions I and II follow

Answer 1

The correct option is A Only conclusion I follows

Some rivers are mountains.
All mountains are plateaus.
$I+A\Rightarrow I$-type of conclusion.
Some rivers are plateaus. (A)
All mountains are plateaus.
No plateau is a sea.
$A+E\Rightarrow E$-type of conclusion.
No mountain is a sea. (B)
Some rivers are plateaus.
No plateau is a sea.
$I+E\Rightarrow O$-type of conclusion.
Some rivers are not seas. (C)
No plateau is a sea.
Some seas are rivers.
$E+E\Rightarrow O_1$-type of conclusion.
Some rivers are not plateaus. (D)
Conclusion I is conclusion (B).