Respuesta :
Answer: Option c: original length of wax.
In an experiment, there are three types of variables: independent, dependent, controlled or constant.
Independent variables are the ones which do not change but can be changed by the scientist. dependent variables are the ones which change when the independent variables change. This is what a scientist observes. Constant variables are the conditions which are kept the same through out the experiment.
In the given experiment, the type of wire used, the length of the wire, thermal conductivity of the wire are independent variables. The time for which the wire is dipped in the hot water, the temperature of the water are controlled variables.
The original length of the wax is a dependent variable. This is because, as the wire is changed, depending upon the thermal conductivity of the wire, the original length of the wax changes.