The correct answer is the following.
What Ferguson claimed about the relative economic development of twelfth and thirteenth-century Italy compared to Song China and the Abbasid Caliphate, was that Italy was far less economically developed.
The situation of Italy in the Middle Ages was different than the economic situation that existed in the Song China and the Abbassid Caliphate. There was this interesting period between the end of the Great Roman Empire and the beginning of the Italian Renaissance, where everything changed, the economy improved and the arts modified the "face" of important city-states such as Florence, where the Medici family invested in artists such as Leonardo Da Vinci.