default option vs choice

default option and choice both are nouns.

Word	Noun	Adjective	Verb	Adverb
default option	Yes	No	No	No
choice	Yes	Yes	No	No

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

default option: an option that is selected automatically unless an alternative is specified
choice: one of a number of things from which only one can be chosen

Other hypernyms of default option include alternative, option.

default option (noun)	choice (noun)
an option that is selected automatically unless an alternative is specified	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

default option (adjective)	choice (adjective)
	of superior grade
	appealing to refined taste