What Is the Difference Between an Initiative and a Referendum

What is the difference between an initiative and a referendum?

A) With an initiative, the people get to vote directly on a question of public policy, whereas with a referendum, the people are only allowed to elect a representative who will vote on ("refer to") a question on their behalf.
B) An initiative is an election for selecting ("initiating") a candidate who will represent a party in the general election, whereas a referendum is a vote by the people on a question of public policy. (Initiatives strengthen parties while referenda weaken parties.)
C) In both initiatives and referenda, the people vote directly on a question of public policy placed on a ballot. The difference is that, in initiatives, government places ("initiates") the question on the ballot, whereas in referenda, the people themselves control what goes on the ballot.
D) In both initiatives and referenda, the people vote directly on a question of public policy placed on a ballot. The difference is that, in referenda, government places the question on the ballot, whereas in initiatives, the people themselves control ("initiate") what goes on the ballot.