Respuesta :
The vulnerability to invaders from the north contributed greatly to the fall of the Song Dynasty.
Answer:
D. The vulnerability to invaders from the north.
Explanation:
Initially, the Song Dynasty had an alliance with the Mongols to maintain the north calm. Both tribes had the same enemy, the Jin Dynasty. But after the Mongols defeated Jin´s the alliance broke up because the Song captured the former imperial capital of Kaifeng. The Mongols then started a campaign against the Song that lasted 20 years and ended up with the creation of the Yuan Dynasty by Kublai Khan.
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