Which of the following is not true about the trochlear nerve

Which of the following is not true about the trochlear nerve

a.Has the longest intracranial course
b.Supplies the ipsilatera superior oblique muscle
c.Only cranial nerve that arises from the dorsal aspect of the brainstem
d.Entres orbit through the superior orbital fissure outside the annulus of zinn

ans:b.Supplies the ipsilatera superior oblique muscle