[单选题]
A polarizer (with its preferred dkz .4u 8i:zpjc co c;-rkkkz.xz6s/)d*4 ;ablqpjf6)s 0y sziirection rotated $30^{\circ}$ to the vertical) is placed in a beam of unpolarized light of intensity 1. After passing through the polarizer, the beam's intensity is
