What are the dependant and independent variables in this bacteria lab

We put different bacteria species on different petri dishes and then used four different disinfectants to put on each culture in a designated quarter of each dish to see if they'd die. What would be the independent and dependent variables in it? I need to write the hypothesis in a statement like, "If ___(dependent variable)__ is related to __(independent variable)___, then ____(expected outcome)___."

Thank you!

The independent variables are the disinfectants. Obviously, the dependent variables will be the bacteria Cultures. you can write your hypothesis now.