Question `19` : `A` Accidental Inventions and Discoveries

`=>`Dựa vào nội dung của toàn bài, ta dễ dàng nhận thấy bài đọc trên nói đến chủ đề "Phát minh và khám phá tai nạn"

Question `20` : `A` It is used for kitchenware nowadays

`=>`Dẫn chứng : By the time his experiment was complete, he had a new invention. It was not a new substance that could be used for refrigeration though. Instead, he had invented Teflon, which is today most commonly used to make nonstick pots and pans in the kitchen.

Question `21` : `B` attempt

`=>`endeavor `=`attempt : nỗ lực, cố gắng

Question `22` : `C` The creator of Coca-Cola

`=>`Dẫn chứng : While he was not successful in that endeavor, he succeeded in inventing Coca - Cola, the world - famous carbonated soft drink. ( Câu cuối đoạn 2 )

Question `23` : `C` a person who made an accidental scientific discovery

`=>`Dẫn chứng : Scientists have also made important discoveries by accident when they were doing experiments. ( Câu đầu đoạn 3 )