Forestland is a planet inhabited by different kinds of creatures. Among other creatures, it is populated by animals all of whom are ferocious. There are also creatures that have claws and some that do not. All creatures that have claws are ferocious. Based only on the information provided above, which one of the following options can be logically inferred with certainty? A. All creatures with claws are animals. B. Some creatures with claws are not ferocious. C. Some non-ferocious creatures are animals. D. Some ferocious creatures are creatures with claws.

GATE 2023 · General Aptitude · Statements Follow · medium

Answer: Option D is the only logically certain inference. Some ferocious creatures are creatures with claws (because claw-creatures exist and all of them are ferocious).

1. Evaluate option A: All claw-creatures are animals: Premise only says Claws -> Ferocious. There is no link from Claws -> Animals. Option A is not supported.
2. Evaluate option B: Some claw-creatures are not ferocious: Premise states all claw-creatures ARE ferocious, so option B directly contradicts a given premise. Option B is false.
3. Evaluate option C: Some non-ferocious creatures are animals: All animals are ferocious means Animals -> Ferocious. A non-ferocious animal would contradict this premise. Option C is false.
4. Evaluate option D: Some ferocious creatures have claws: The passage states claw-creatures exist. All of them are ferocious. Therefore there exist creatures that are both ferocious AND have claws => 'Some ferocious creatures have claws' is TRUE with certainty.