Question

Some birds are animals. All animals are rivers. Some rivers are lions.
Conclusions:
(I) Some lions are animals
(II) Some rivers are birds
(III) No animal is a lion
Which conclusions logically follow?

• A. Only (II) follows
• B. Only either (I) or (III) follows
• C. Only (II) and (III) follow
• D. (II) and either (I) or (III) follow

Hint:

In syllogisms, "either-or" follows only when exactly one of the two conclusions must be true.

Answer 1

The Correct Option is D

Step 1: Analyze each
conclusion separately.

(I) Some lions are animals: not directly mentioned — possibility but not certainty.
(II) Some rivers are birds: Some birds are animals, and all animals are rivers. So some rivers can be birds → logically follows.
(III) No animal is a lion: Not directly stated. Could be true if (I) is false.
Step 2: Apply Either-Or Rule.
Between (I) and (III), either one is true (but not both). Hence, "either (I) or (III)" follows.
Step 3: Final decision.
Thus, (II) and either (I) or (III) follow.