Question

practice it! which of the following is the independent variable (or test variable) in the flu - d12 investigation? the rate of viral infection the amount of virus killed the exposure to ultraviolet light the temperature of the environment

Explanation:

An independent variable is the factor that is deliberately changed or manipulated in an experiment. In a Flu - d12 investigation related to virus, exposure to ultraviolet light can be a factor that researchers can control to see its effect on viral - related outcomes like rate of infection or amount of virus killed. The rate of viral infection and amount of virus killed are likely dependent variables that respond to changes. Temperature of the environment is also a general factor but not as directly related to Flu - d12 as UV light exposure in a context where UV light's impact on virus is being studied.

Answer:

the exposure to ultraviolet light