couldn't find any appropriate solution from the internet.. :( 

12. A new restaurant is interested in determining the best time-temperature combination for roasting a five-pound cut of lamb. The times to be tested are 45 minutes, 60 minuets, and 90 minutes at temperatures of 350 degrees Fahrenheit and 425 degrees Fahrenheit for each time, with the exception of the 90 minute-425 degree combination. That combination is being eliminated because it will overcook the lamb, which leaves five combinations remaining. From 10 identical cuts of lamb, 2 are randomly selected to roast using each of the time-temperature combinations in the same oven. The quality of the finished product is evaluated for each roast. Which of the following is true? 

(A) The explanatory variable is the quality of the finished lamb 

(B) The response variable is the roasting temperature for the lamb. 

(C) If the experiment is repeated, identical results will be expected. 

(D) There should be a control group (i.e., a group in which no treatment is given.) 

(E) The two cuts that are being roasted for each time-temperature combination are an example of replication. 

I'm confused between C and E. 

Can you expain this?

Thanks in advance!