Why Do Winning Candidates Claim a Mandate Even Though Political

Why do winning candidates claim a mandate even though political scientists generally discredit the mandate theory of elections?

A) Politicians think that political scientists do not understand how things actually work.
B) Voters do not necessarily prefer all of the winning candidate's issue positions.- Consider This: Election promises should be carried out by the winning party or candidate.
C) Winning candidates want to justify their policy proposals by claiming that the public supports them.
D) Winning candidates are not well versed in the political science literature.