What may be most harmful to our teeth?

Question 39. What may be most harmful to our teeth?
A. red rice
B. raw vegetables
C. sweet things
D. fresh fruit
Question 40. The best title for the passage would be
A. "How to keep our teeth ever white"
C. "How to clean our teeth"
Read the following passage and mark the letter A. B. C. or D on your answer shee
B. "How to make our teeth nicer"
D. "How to keep our teeth healthy"