Concept: 1) We have to check the conclusions are
100% match with the statement. If the conclusion is
100% match with the given statement then the conclusion is true. If there is a
1% chance of not following the statement then the conclusion is considered to be false.
2) The possibility case can be considered to be "false" in "definite case".
3) In Possibility case, either "can" or "possible" word must be present.
The least possible Venn diagram as per the given statement is as follows:
Conclusion: I. Some cats are rats
→ True (as "all cats are dogs and all dogs are rats" given so, some cats are rats true it is definite, hence, true)
II. No cats are rats
→ False (as "all cats are doges" and "all dogs are rats" given so cats are a part of rats also thus, no cats are rats it is definitely false)
Hence, the correct answer is "Only conclusion I follows". Some cats are rats → All cats are dogs and all dogs are rat so all cats are rats and also if all cats are rats then some cat are rats is definite true.
Some cats are rats
⇒ All cats are dogs and all dogs are rat so all cats are rats and also if all cats are rats then some cat are rats is definite true.