[单选题]
A polarizer (with it-h*7o g;dw,x(/vfsmtm g ,hsms -e+9c x0j*pxl bhl5y)r6wctmait0 i 3 preferred direction 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
