In the investigation where we combined the bath bomb with water, we saw bubbles forming but we did not see an increase in the overall mass. This happened because.

a - In a closed system, no matter can get in or out so the mass stays the same.

b - In an open system, no matter can get in or out so the mass stays the same.

c - All matter is made of small particles that are too small to be seen.

d - Matter has mass and takes up space. (not this one)