I am pretty sure its D. I am not 100% positive but I read an article and that appears to be correct.
Slavery for sure. I believe the second one is economic differences between the North and the South.
A nonstop flight to Europe
<em>the Gupta empire continued resisting the invasions of the Huns</em>, a nomadic people who lived in Central Asia and Eastern Europe, between the 4th and 6th century.
The Hun invaders were defeated by Bhanugupta in 510. They were also defeated and driven out of India in 528 by king Yashodharman, and by emperor Narasimhagupta.
It is said that such invasions had long-term effects on India, contributing to the end of this classical Indian civilization.
