C34: Suppose we cover each slit in Young's experiment with a polarizer such that the polarization transmitted by each slit is orthogonal to that transmitted through the other. On a screen behind the slits, we see:

1. the usual fringe pattern.

2. the usual fringes shifted over such that the maxima occur where the minima used to be.

3. nothing at all.

4. a fairly uniformly illuminated elongated spot.