Answer: To cut off New England from the rest of the colonies.
The answer you're looking for is c.
The Long March (October 1934 – October 1935) was a military retreat undertaken by the Red Army of the Communist Party of China, the forerunner of the People's Liberation Army, to evade the pursuit of the Kuomintang (KMT or Chinese Nationalist Party) army.
Because they feel like they must take out other countries before they get taken out (survival of the fittest)