The answer is B, Degradation
I had this question in my quiz and got it right.
C, caesar
He was the only one who go power during that time.
Well one, I learned that you shouldn't judge someone based on their race, ethnicity, and social structure. Also, your race, ethnicity, and social structure makes you who you are. Hope I helped!! :)
The best explanation why the area between Spain and Gaul was not part of the Roman empire until that later period was a culmination from both undesireability and difficulty in accessing this region due to its mountaineous nature. So I would wager the answer being both C and D - undesireability and difficulty in access.