What caused the rifts in the democratic party in the 1968 election?

In the 1968 election, Hubert Humphrey won the Democratic Party nomination despite the fact that he had done poorly in all the primaries. Because of that, many supporters of antiwar candidates like Eugene McCarthy and Robert Kennedy refused to vote. Others voted as a protest to the segregationist George Wallace and others voted for Richard Nixon.

b)

it created free trade throughout the colonial territories.

what are the options so i can answer it