Question

Choose the set of three statements which are most logically related:
Statements:
A. No fishes breathe through lungs.
B. All fishes have scales.
C. Some fishes breed upstream.
D. All whales breathe through lungs.
E. No whales are fishes.
F. All whales are mammals.

• A.
• B.
• C.
• D.

Hint:

In negative statement chains, confirm that exclusions in one statement align with inclusions in another to avoid contradictions.

Answer 1

The Correct Option is C

Take A (“No fishes breathe through lungs”), D (“All whales breathe through lungs”), and E (“No whales are fishes”):
- From A, any creature breathing through lungs is not a fish.
- From D, whales breathe through lungs, so whales are excluded from being fishes.
- E explicitly states “No whales are fishes,” which directly aligns with the deduction from A and D.
These three statements reinforce each other logically without introducing unrelated properties like scales or breeding behavior.