Question

Assertion: Decay of teeth is due to the decrease in pH in the mouth.

Reason: Acids released slowly destroy the enamel coating which protects teeth.

• A. Both assertion and reason are correct and the reason is the correct explanation of the assertion.
• B. Both assertion and reason are correct but the reason is not the correct explanation of the assertion.
• C. The assertion is correct but the reason is incorrect
• D. The assertion is incorrect but the reason is correct

Answer 1

The correct option is A

Both assertion and reason are correct and the reason is the correct explanation of the assertion.

Explanation for the assertion statement:

This statement is correct as-

The micro-organisms present in the mouth convert some sugar that we eat into acids which decrease the pH of the mouth.

Explanation of the reason statement:

This statement is correct as-

1. Teeth have an enamel coating containing calcium appetite which is a form of Calcium Phosphate (Ca₃(PO₄)).
2. Acids produced by the microbes react with the Calcium phosphate present in the enamel and destroy it.

Thus, both assertion and reason are correct and the reason is the correct explanation of the assertion.

Therefore, option A is correct.