The answer is D. the Battle of Hastings
Got this answer by reading through the material.
Classical art is the paintings, sculptures and architectures of Ancient Greece and Rome.
He thinks that it's important for city people to understand the process of food making and to eat responsibly because if they are not connected to their food and don't think about it, they won't appreciate the farmers who worked hard to make it. If people eat responsibly there will be a greater democracy according to him.
The answer is A) concentrated within a small upper class
Special words or expressions that are used by a particular profession and are difficult for others to understand are called "jargon," since they are often only understood by people "in the know".