Final answer:
The colony of Plymouth became self-sufficient through self-rule, education and industry, and reliance on fishing and agriculture.
Step-by-step explanation:
The colony of Plymouth became self-sufficient through a combination of factors. First, the Pilgrims drafted the Mayflower Compact, declaring that they would rule themselves. This led to the establishment of formal self-rule among the Pilgrims. Second, education and industry became important aspects of life in their colonies, incentivized by the Puritans' belief that a working knowledge of Scripture was necessary for church membership. Finally, the colony's reliance on fishing and agriculture, particularly the cultivation of corn, helped provide a stable food source.