Which of the following terms best describes a government in which all members of a society are allowed to vote and hold office?

a. universal suffrage

b. theocracy

c. Sharia law

d. dictatorship

This describes an universal suffrage - the word "universal" means "for all people" so ut means 'the right to vote for all people".

Theocracy and Sharia law are both forms of government related to religion and a dictatorship is a form of absolute power held by one person or a group of people.