If Earth's Axis of Rotation Suddenly Became Perpendicular to the Plane

Multiple Choice

If Earth's axis of rotation suddenly became perpendicular to the plane of its orbit, the most predictable effect would be

A) no more night and day.
B) a big change in the length of the year.
C) a cooling of the equator.
D) a loss of seasonal variation at high latitudes.
E) the elimination of ocean currents.