option vs obverse

option and obverse both are nouns.

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

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

option (noun)	obverse (noun)
the act of choosing or selecting	the side of a coin or medal bearing the principal stamp or design
one of a number of things from which only one can be chosen	the more conspicuous of two alternatives or cases or sides
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