Which minor party has never been active in the united states
a. reform
b. conservative
c. bull moose
d. green

Answer;
B. Conservative party 

Conservative party is the minor party that has never been active in the united states.

Explanation;
Minor parties are very important as they serve an important role in the political system by forcing major parties to address new issues they might not have previously addressed. Examples of minor parties in the U.S. include; Green party, reform party, conservative , bull moose party among others, other than the two major parties. 
The Republican and the Democratic party are the major parties in the U.S.