Answer:
D: pick a running mate who, if elected, will be the vice president
Step-by-step explanation:
For one to be able to run for an election, the person must belong to a political party which is an umbrella body or group of individuals with broad common interests who organize to nominate candidates for office, win elections, conduct government, and determine public policy.
Primary Election are Elections conducted where voters choose a candidate from within a party e.g. democratic party, to run in the general election.
General Election is conducted to select officers for local, county, state, and federal offices. Elections for county, state and federal offices are held in the US in November of even numbered years. For the office of the presidency, one must have a running mate who is going to be the Vice president. The position is selected mostly after party primaries where the main president candidate has being selected.