What Event in France Shifted Voters Toward Right-Wing Positions on Immigration

What event in France shifted voters toward right-wing positions on immigration?

A) riots in impoverished suburbs bordering French cities
B) the assassination of filmmaker Theo van Gogh
C) a terrorist attack at a French elementary school
D) bombings on Parisian buses and subways
E) the U.S.claim that Iraq had developed weapons of mass destruction