In an ? primary, voters choose delegates who will represent them at a party convention.

Indirect primary is the correct answer.

Explanation:

Indirect primaries are the elections used in many states  for the presidency of the US. The voters in the primaries select candidates to attend the national political convention and pledged to cast their ballots as per the choice of their voters. The rules for deciding the delegates are decided by political parties and vary from state to state. Winner takes all is the criteria for selection of the candidates.

In an indirect  primary, voters choose delegates who will represent them at a party convention.

length of the cultivating season was not a problem of new england agriculture

silk

indigo  

rice

all the other answers are wrong