Respuesta :
The Mongols repeatedly fail to conquer the Song dynasty before Kublai Khan's conquest because the Song army had trebuchets. Thus, option first is correct.
What was Song Dynasty?
Song Dynasty was one of the longest dynasty of China which began its governance from 960 and collapsed in 1279. It was the imperial dynasty of China.
The dynasty was established by Emperor Taizu of Song after he usurped the Later Zhou throne. The remainder of the Ten Kingdoms were subdued by The Song, bringing an end to the Five Dynasties and Ten Kingdoms period.
It was very difficult to conquer the song dynasty of China due to its location, which was strategically designed.
Xiaoguang made the Song dynasty challenging to overthrow; this made it crucial for Kublai to seize and control this city. Because the Han River was a significant tributary of the Yangtze River, the city protected the South Chinese waterways.
Therefore, it can be concluded that option first is correct.
Learn more about Song Dynasty here:
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