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Assertion (A) : Tooth decay starts when ...

Assertion (A) : Tooth decay starts when the pH of the mouth is lower than 5.5. Reason : Bacteria present in mouth produce bases.

A

Both ‘A’ and R are correct and ‘R’ supports ‘A’.

B

Both ‘A’ and ‘R’ are correct and ‘R does not supports A

C

‘A’ is wrong. ‘R’ is correct.

D

‘A’ is correct, ‘R is wrong,

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