The BEST explanation for why Confucianism contributed to territorial expansion into southeast Asia, Korea, and Japan was that

AConfucianism stressed war and aggression and territorial expansion followed.
Bthe Emperor worked to decentralize his empire and sent Confucian scholars to new areas to rule.
CChinese merchants were less valued in society and therefore traders had more freedom to travel and expand markets.

Eliminate

DConfucian scholars were encouraged to take on missionary-like work and to preach Confucius’ teachings in new lands.

Verified Answer :

Answer:  C. Chinese merchants were less valued in society and therefore traders had more freedom to travel and expand markets.

Explanation: Confucianism brought a stability into a country which had been effected in many ways from previous changeovers in dynasty's. Confucius believed that every person had there place in society. He enforced through his philosophy, and turned Ancient China into a structured society. This structured society was based on work/effort given by the social class. For example- The merchants were at the bottom of this system even though many were wealthy, they didn't labor like farmers did.