“Clerk” means the clerk or secretary of a commission, county, city, or district, or the clerk or secretary of the legislative body of a county, city, or district. Where the office of county clerk is separate from the office of the clerk of the board of supervisors, “clerk” means the clerk of the board of supervisors. Where the office of county clerk is separate from the office of the registrar of voters, “clerk” means the registrar of voters with respect to all duties pertaining to the conduct of elections and the county clerk with respect to all other duties.