alternative vs choice

alternative and choice both are nouns.

Word	Noun	Adjective	Verb	Adverb
alternative	Yes	Yes	No	No
choice	Yes	Yes	No	No

As nouns, alternative and choice are synonyms defined as:

alternative and choice: one of a number of things from which only one can be chosen

Other synonyms of alternative include option.

alternative (noun)	choice (noun)
one of a number of things from which only one can be chosen	the act of choosing or selecting
	the person or thing chosen or selected
	one of a number of things from which only one can be chosen

alternative (adjective)	choice (adjective)
necessitating a choice between mutually exclusive possibilities	of superior grade
serving or used in place of another	appealing to refined taste
pertaining to unconventional choices