The answer is that early on the English were looking for a "Northwest Passage". This would be a shorter trade route to East Asia. For a long time it was believed that there was a large body of water in North America that would lead to the Orient. The English were interested in the raw materials that they could find in North America, including the islands of the Caribbean.
C)They allow multiple votes, from multiple voices to be heard
Political parties foster multiple elections. Most famously, the primary and general presidential elections. In the primary election the candidate that will represent each political party is voted into candidacy for the general election. In the general election voters choose between the candidate from each party to become president.
