Answer: Option (A) is the correct answer.
Explanation:
Starter bacteria helps in conversion of milk sugars into lactic acid. This also helps in development of flavor in aged cheese that is used in many food items.
Most of the starter bacteria is made by using bacteria such as lactococcus and lactobacillus. Whereas initial cheese ripening is done by streptococci.
Thus, we can conclude that out of the given options cheese on pizza is the product which is made using bacteria.