Get 20 RRB NTPC mocks for just Rs. 149. Enroll now
Tooth decay starts when the pH of the mouth is .............
more than 5.5
less than 5.5
less than 4.5
more than 4.5
Create a FREE account and get:
Ask doubts feature is currently unavailable for you. You can reach us at email@example.com for any further details/doubts.
Boost your Prep!