Which statement describes a key difference between sunni muslims and shia muslims?
a. compared with sunni muslims, shia muslims are the majority group in most middle eastern countries
b. unlike sunni muslims, shia muslims did not establish any gunpower empires
c. compared with shia muslims, sunni muslims grant less authority to descendants of muhammad
d. unlike shia muslims, sunni muslims observe the five pillars of islam