possible action vs choice

possible action and choice both are nouns.

Word	Noun	Adjective	Verb	Adverb
possible action	Yes	No	No	No
choice	Yes	Yes	No	No

As nouns, choice is a hypernym of possible action; that is, choice is a word with a broader meaning than possible action:

Other hypernyms of possible action include alternative, option.

possible action (noun)	choice (noun)
a possible alternative	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

possible action (adjective)	choice (adjective)
	of superior grade
	appealing to refined taste