Explain which of the Chinese Dynasty (Shang,
Zhou, Qin & Han) have the most significant
impact on modern China?

Qin & Han

Explanation:

The Qin Dynasty was followed by the longer-lived Han Dynasty, which expanded territory, centralized governmental authority, and created a bureaucracy that lasted for two millennia.

the mongolian invasion of china and central asia resulted in a disruption of the silk road as the chinese garrisons lost support from the chinese kingdoms which fell under the mongols. however, as the mongols established a formal dynasty in china, the successors of genghis khan restored the garrisons along the silk road allowing the safe travel caravans again.

your mothers brothers brother in law would be your father.