Are you logical? ‘Wason’s Four-card Task’ (あなたは論理的?「ウェイソンの四枚カード問題」)

“Are you logical? ‘Wason’s Four-card Task'”
Hello, everyone.
I’m a software development engineer. The ability to think logically is important for engineers.
Today, I’d like to introduce a logical puzzle which tests your logical thinking skills. It’s known as “Wason’s Four-card Task”.
Four cards are on a table.
[D] [A] [7] [4]
Each card has a letter on one side and a number on the other side.
The question is, which of these cards would you need to turn over in order to know whether the following statement is true or false?
The statement is: “If a card has a vowel on one side, then it has an even number on the other side.”
Got it? What’s your answer?
# For your information, Wason gave this test to 128 University-educated adults, and only 5% gave the proper answer.
[D] [A] [7] [4]
命題: 「カードの片面に母音が書いてあれば、その裏面には偶数が書かれている」
# ちなみに、ウェイソン はこのテストを 128 人の大学を出た成人に行いましたが、正解者はたった 5% でした。