Fact 1 : All birds can fly.
fact 2. Some birds build nests.
fact 3 : Penguins are birds.

Which of the following must be a fact?

1. All birds that build nests can fly.
2. Penguins build nests.
3. Penguins can fly.

Hi sir, but as per fact number 1, all birds can fly. So the birds building nests will also fly. So why statement 1 can't be true?

Based on the rules of formal deductive logic, the correct answer is 3. Penguins can fly.

In a syllogism problem, you must accept the given premises as absolute truth, completely ignoring real-world biology. Fact 1 establishes the universal rule that all members of the bird category possess the ability to fly.

Fact 3 explicitly places penguins inside that exact bird category.

Therefore, the correct answer is 3.

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