Independent variable I believe is the correct answer. Since that is what is being changed.
B, a drug like that could be steroids
B, C and D. Though if the question wants you to pick one I would go with C
The maximum amount of time the chicken should cook from 135*F to 70*F is 4 hours.
It takes resources when there are more animals it takes more food then when you run out of food you will have to buy more which you will run out of money its all about money without money animals will starve.
Your answer is takes resources.