option vs decision

option and decision both are nouns.

Word	Noun	Adjective	Verb	Adverb
option	Yes	No	No	No
decision	Yes	No	No	No

As nouns, decision is a hyponym of option; that is, decision is a word with a more specific, narrower meaning than option:

option (noun)	decision (noun)
the act of choosing or selecting	the act of making up your mind about something
one of a number of things from which only one can be chosen	the trait of resoluteness as evidenced by firmness of character or purpose
the right to buy or sell property at an agreed price; the right is purchased and if it is not exercised by a stated date the money is forfeited	a position or opinion or judgment reached after consideration
	the outcome of a game or contest
	(boxing) a victory won on points when no knockout has occurred