Waive means to refrain from insisting on or using something whereas retain means continue to have (something); keep possession of which is opposite in the meaning. Hence, a correct option.

Zealous means having or showing zeal whereas apathetic means showing or feeling no interest, enthusiasm, or concern which is the opposite of Zealous. Hence, the correct option.

Eternal means lasting or existing forever; without end or beginning whereas ephemeral means lasting for a very short time which is the opposite of eternal. Hence, a correct option.

Cautious means attentive to potential problems or dangers whereas foolhardy means recklessly bold or rash which is the opposite of cautious. Hence, the correct option.

Antipathy a deep-seated feeling of dislike; aversion whereas affection means a gentle feeling of fondness or liking which is the opposite of antipathy. Hence, the correct option.

Hysteria means exaggerated or uncontrollable emotion or excitement whereas serenity means the state of being calm, peaceful, and untroubled which is the opposite of hysteria. Hence, the correct option.

Sham means a thing that is not what it is purported to be whereas authentic means of undisputed origin; genuine which is the opposite of sham. Hence, the correct option.

Paucity means the presence of something only in small or insufficient quantities or amounts; scarcity whereas affluence means abundant wealth which is the opposite of paucity. Hence, the correct option.

The word optimistic means tending to expect favorable outcomes. The opposite of optimistic is pessimistic or expecting unfavorable outcomes. Because cynical means bitterly distrusting or pessimistic, it is the correct option.

It means clearness or lucidity as to perception or understanding; freedom from indistinctness or ambiguity. This is the opposite of distortion.

It means attentive, aware, or careful.This is the opposite of slumber.

Fickle means changing frequently, especially in regards to one's loyalties, interests, or affection whereas constant means occurring continuously over a period of time which is the opposite of fickle. Hence, the correct option.

Lucrative means producing a great deal of profit whereas unprofitable means not producing good or helpful results which is the opposite of lucrative. Hence, the correct option.

Notorious means famous or well known, typically for some bad quality or deed whereas inconspicuous is not clearly visible or attracting attention which is the opposite of notorious. Hence, a correct option.

Aggravate means to rouse to exasperation or anger or provoke whereas delight means to please someone greatly which is the opposite of aggravate. Hence, the correct option.