MCQ
For question two statements are given $-$ one labelled Assertion $(A)$ and the other labelled Reason $(R).$ Select the correct answer to these questions from the codes $\ce{(a), (b), (c)}$ and $(d)$ as given below: Assertion : Tooth decay starts when the pH of the mouth is lower than $5.5.$
Reason : Enamel starts corroding below $5.5. \ce{pH}.$
  • Both $A$ and $R$ are true, and $R$ is correct explanation of the assertion.
  • B
    Both $A$ and $R$ are true, but $R$ is not the correct explanation of the assertion.
  • C
    $A$ is true, but $R$ is false.
  • D
    $A$ is false, but $R$ is true.

Answer

Correct option: A.
Both $A$ and $R$ are true, and $R$ is correct explanation of the assertion.

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