Correct option is B
Inevitable means certain to happen; unavoidable.
Synonyms: Unavoidable, inescapable, certain.
Antonyms: Avoidable, uncertain, preventable.
Meanings of all four options:
Immemorable: Not memorable; not easily remembered or noteworthy.
Undeniable: Unable to be denied or disputed; unquestionably true or certain.
Adventurous: Willing to take risks or try out new methods, ideas, or experiences.
Escapable: Able to be avoided or evaded.