What is the primary area of research for Jonathan Harris, a professor at Royal Holloway, University of London?

A. Byzantine History 900–1460; relations between Byzantium and the west, especially during the Crusades and the Italian Renaissance
B. Modern Greek History 1800–2000; the Greek War of Independence
C. Medieval European History 1000–1500; the rise of the Holy Roman Empire
D. Ancient Roman History 500 BCE – 500 CE; relations between Rome and Egypt
Answer: 