In the Middle Ages (about 476 ~ 1453), when Western Europe just entered the feudal society in the 5th century, China had already completed the course of the feudal society of about 1000 years.
During this period, China experienced
Eastern Jin Dynasty 3 17-420
Sixteen countries in 304-439.
Southern and Northern Dynasties
Southern Dynasties
Song Dynasty 420-479
Qi 479-502
Beams 502-557
Chen 557-589
Northern Dynasties
Northern Wei Dynasty 386-534
Eastern Wei 534-550
Northern Qi Dynasty 550-577
Western Wei Dynasty 535-557
Northern Zhou 557-58 1 year
Sui 581-618
Tang 6 18-907
the Five Dynasties
Back beam 907-923
Late Tang 923-936
Late Jin Dynasty 936-946
947-950 in the later Han Dynasty
Last week 95 1-960
Ten kingdoms from 902 to 979
Liao 916 ——1125.
Northern Song Dynasty 960- 1 127
Southern Song Dynasty1127-1279.
Xixia 1038- 1227
Gold1115-1234.
Yuan1271-1368.
Ming1368 ——1644.
The feudal system reached its peak in the Qing Dynasty, but the Qing Dynasty did not belong to the category of the Middle Ages. So AB is all wrong.
It is also wrong to think D, because most theorists called capitalism appeared in18th century,19th century and 20th century, such as the industrial revolution and European imperialism (such as Smith and Ricardo), the Great Depression (such as Keynes) and the Cold War (such as Hayek and Friedman).
There was no concept of capitalism in the Middle Ages.
So, choose C.