Answer the following question given this paragraph: 

Bacteria can be used to make cheese from milk. The bacteria turn the milk sugars into lactic acid. The acid is what causes the milk to curdle to form cheese. Bacteria are also involved in producing other foods. Yogurt is made by using bacteria to ferment milk ( Figure below ). Fermenting cabbage with bacteria produces sauerkraut.


Q: Bacteria can be used to make cheese from milk. the bacteria turn the milk sugars into what?

 Choices:

- acetic acid

- ionic acid

- hydrochloric acid

- lactic acid

A:
lactic acid
