catalase experiment

food rate of fizzing (1-10)
boiled potato 0
raw potato 4
cooked liver 1
raw liver 10

the table above shows the results of an experiment done by juan and cindy. juan and cindy placed hydrogen peroxide on several food samples and recorded the relative amount of fizz that each produced. the fizz was produced by oxygen bubbles released by the action of the enzyme catalase, which is found in almost every living cell. which of these is a valid conclusion from their data?