A student placed four drops of water on a fresh slice of bread. Next the wet bread was placed inside a plastic bag and sealed up tight. After that, the student placed the sealed bag of wet bread on a balance. The mass is recorded as 20 grams. After 10 days, the student observed many types of mold growing on the bread and inside the sealed bag. The pictures show the student’s experiment.
Set up: A bread plus four drops of water plus a plastic bag equals to 20 grams.

Result: Bread in side the plastic bag equals to: ____ grams.


Predict the mass of the sealed bag of moldy bread.

A. 15 grams

B. 20 grams

C. 22 grams

D. 25 grams