Is there a reasoning question to find a flaw!!

If B is wrong, then B is the last and D is the last place. So B is right.

If D is wrong, then D is not the last place, A is the first place, and B and C both say that they cannot be the last place, so there is no last place, so D is also right.

If C is wrong, then C must be the first or last, which conflicts with A and D, so C is also right.

Here's an analysis of why A is wrong.

If A is wrong, then D is the last place, A is not the first, C is not the first and is not the last, then A and C can be one of the 23 places, and B is the first place. So A can be wrong.

Thank you, welcome to ask, absolutely original!

Reasoning, if A is wrong, then the first is not A, and the other three are correct, then B is the first, A C is either the second or the third, and D is the last anyway. If B is wrong and everyone else is right, then B is the last, which causes D to be wrong as well, so this situation does not match. If C is wrong, then C is either the first or the last, which also leads to a contradictory result with others, which is inconsistent.

If D is wrong, no one is last, and it doesn't match.

Therefore, the result is either BACD or BCAD

A** is wrong, it should be that only A** is wrong, and other people's ** can be right, because there can only be one person** who is wrong, D is the last place, B is the first place, A is the 2nd or 3rd place, and C is the 2nd or 3rd place

If B or C is wrong, then D is also wrong, and it is not relevant, so A is wrong, and then BCAD is obtained according to the conditions

Solution: If D** is wrong, then naturally another player ** is wrong, otherwise there will be no last place; If C** is wrong, he deserves first or fourth place in this competition, but in this case, the first and fourth places have been occupied by A and D respectively; If b** is wrong, then he can only be the fourth, here d also becomes **, but according to the conditions, there is only one person who is wrong.

Therefore, the only mistake can be A, and he should be the second or third.

In this way, the ranking could be:

1) 1st place: B, 2nd place: A, 3rd place: C, 4th place: D;

2) 1st place: B, 2nd place: C, 3rd place: A, 4th place: D.

Typical elimination problem. From the parentheses, it can be seen that the landlord has made some exclusions. However, the landlord ignores the hidden condition - C has a wife, and the farmer is not married, so the farmer is not C, since C is not a farmer, a doctor, and Jing Cha, then C must be a carpenter.

Another hidden condition is that A has a son, and the peasant is not married, so the peasant is not A. Since the peasants are not A, C, or B, then the peasants are D. Now only the identities of the two are undecided, and A is not a doctor, so A is Jingcha, so B is a doctor.

To sum up, A is Jing Cha, B is a doctor, C is a carpenter, and D is a farmer.

Suppose the poem is right, then.

The poem said: Zhi likes the blue Lan says: The chi doesn't like the poem Peng said: The chi doesn't like the blue

Suppose for blue, then.

Lan said: Zhi doesn't like poetry, but Peng said: Zhi doesn't like Lan; The poem says: Zhi likes blue; Can't tell.

Assuming that Chi is right, then.

Peng said: Zhi doesn't like blue Lan said: Zhi doesn't like poetry, not necessarily, poetry said: Zhi likes blue

To sum up: Chi likes blue.

The poem contradicts the words of Peng. So one of them must have told a lie. So Blue is telling the truth. That's why Chi doesn't like poetry.

This is all we know. So Chi may like Blue, or he may like Peng.

If the title is that only one of them tells the truth, then Chi likes poetry. The reason is that Lan is telling a lie.

The poem is the opposite of Peng, so it is true and false, as for who is true and who is false, it doesn't matter, Lan must be true.

So Chi can be like Blue, or Peng, both are true.

The on-site inspection of the lunch box coffee was not poisonous, and it was basically determined that the president's wife was not suspected of committing a crime.

The vice president drank coffee in the president's office, and the secretary said that he had sent two cups of coffee to the president's office, so the secretary should give the president and the vice president a cup of coffee each when he came into the office.

The only person who had the opportunity to take one thing from the scene was the vice president, who took the poisoned coffee that the president drank and left his own coffee that was not poisoned at the scene, so there was no poison in the coffee that was checked, because the poisonous one was taken by the vice president.

** is the vice president.

If there are 10 non-officers in the original unit, including 4 high-wage officers, 6 low-wage officers, 8 officers, 1 high-wage officer, and 7 low-wage officers, Xiao Zhang Xiaowang may be a high-wage non-officer, a low-wage non-officer, or a low-wage non-officer, and a low-wage officer, then BCD excludes and selects A

I've rubbed Conan too much.