With which statement would advocates of the scientific method agree? a) new ideas about the world must be supported by established theory. b) faith can be used to reconcile conflicts between observation and ideology. c) the testing and retesting of ideas provides the best approach to solving problems. d) truth about the conditions of life is found in the teachings of the church.

C) The testing and retesting of ideas provides the best approach to solving problems.   
The scientific method relies upon gathering of data. Creation of a hypothesis that can both predict new data and is potentially falsifiable. Gathering of new data that is predicted by the hypothesis, or indicates that the hypothesis is incorrect, in which case modify the old hypothesis, or create a new one that matches the known data. Now with that in mind, let's look at the choices and see what fits.  
A) New ideas about the world must be supported by established theory.  * This option assumes that established theory comprising the whole of all possible theories. This is in direct conflict with the scientific method and is therefore a bad choice.  
B) Faith can be used to reconcile conflicts between observation and ideology.  * The scientific method relies only on the observed data. As such, using faith to reconcile differences between observations and what one thinks things should be is in conflict. So this too, is a bad choice.  
C) The testing and retesting of ideas provides the best approach to solving problems.  * This is a nice truthful summary of the scientific method. So this is the correct choice.  
D) Truth about the conditions of life is found in the teachings of the Church. * This is not the scientific method. So this is a bad choice.