OpenStudy (anonymous):

Pope Urban II granted the Byzantine emperor help against the Seljuq Turks because a. the Seljuq Turks were holding citizens of the Byzantine Empire prisoner. b. the Seljuq Turks were enslaving citizens of the Byzantine Empire. c. the Seljuq Turks had control of the Holy Land. d. the Seljuq Turks gained control of the Byzantine Empire.