Practice mode Reading Comprehension

According to the passage about tooth enamel, what produces the acids that damage teeth?

Read the passage: Tooth enamel, the thin outer layer of each tooth, is the hardest substance in the human body. Yet it can still be damaged, and unlike bone, it cannot repair itself once it is badly worn away. The main threat comes from plaque, a sticky film of bacteria that builds up on teeth. When we eat or drink sugary foods, these bacteria feed on the sugar and produce acids that slowly dissolve the enamel, eventually creating holes known as cavities. Brushing twice a day with a fluoride toothpaste helps in two ways: it removes plaque, and the fluoride makes enamel more resistant to acid. Cutting down on sugary snacks between meals also reduces the number of acid attacks teeth must endure.

Correct answer B. Bacteria in plaque feeding on sugar

Explanation

The passage explains that bacteria in plaque feed on sugar and produce acids that slowly dissolve the enamel, eventually creating cavities.

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Answer checked 11 October 2026 How we write and check questions

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What does the passage about Farhan’s restaurant in Hyderabad suggest?

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Correct answer C. Offering fewer dishes can improve both quality and profits.

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Question 02 Reading Comprehension

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Correct answer C. Air expanding violently after being heated by lightning

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Question 03 Reading Comprehension

Based on the passage about bamboo, why might designers see it as a good alternative to timber?

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Correct answer D. It can be harvested repeatedly and regrows quickly without replanting.

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Question 04 Reading Comprehension

In the passage about the electronics shop in Rawalpindi, what does the word ‘lure’ most nearly mean?

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Correct answer C. Something used to attract people

Open question

According to the passage about tooth enamel, what produces the acids that damage teeth?

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