The correct option is option A ("It cannot be taken away by a government").
The nature of inalienable rights, as introduced in the Declaration of Independence by Thomas Jefferson, is guaranteeing the safety of certain liberties given to the population. These contemplated the most basic needs for the welfare of an individual, such as the rights of "life, liberty and pursuit of happiness". The quality that best characterizes a right as inalienable, is that it cannot be taken away by any government or legal power.
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