Fact 1: Sugar causes food to taste sweet.

Fact 2: Too many sweets can also cause tooth decay and unhealthy gums.

Given the two facts above, answer the question "What causes tooth decay and unhealthy gums?" with the following options: 
- meat
 - worms
 - salt
 - smoking
 - sugar
 - vegetables
 - mildew
 - Alcohol


 

     sugar    