The prefix sub- means beneath or under. “Subliminal” means occurring beneath the surface of your understanding; this is closest in definition to “unconscious.” “Conscious” means aware, so “unconscious” means an understanding you are not aware of. “Unconscious” can also mean passed-out. To provide further help, “posthumous” means occurring after death; “outlying” means remote; “remonstrate” means argue, protest; “comparable” means similar, able to be compared. 

“Innocuous” means not harmful, which is identical in definition to “benign.” Here might be a good time to examine the differences between the prefixes "ben-" and "mal-." "Ben-"means good, positive, helpful, etc. and "mal-" means bad, evil, hurtful, etc. “Malevolent” means evil or wicked-natured and “benevolent” means good-natured, while “malfeasant” means exhibiting bad behavior and “malodorous” means bad-smelling.

“Malcontent” means not content, dissatisfied. To provide further guidance, "whimsical" means quirky and silly; "mercurial" means enigmatic and hard to predict; "nostalgic" means having fond memories about the past; "obsequious" means flattering.

"Incredulous" means disbelieving or doubtful of the credibility of something. Thus, the best answer choice is "disbelieving." For instance, if a child gives an incredulous look about whether drinking tea will help his or her cold, it means that the child is doubtful whether the tea can help him or her.

"Unruly" is an adjective that means "disorderly and disruptive and not amenable to discipline or control." So, we need to pick out an answer choice that means something like "disruptive." "Well-behaved" cannot be the correct answer, then, because "well-behaved" is an antonym of "disruptive." "Rowdy," however, is an adjective that means "noisy and disorderly," and because "rowdy" is the answer choice closest in meaning to "unruly," "rowdy" is the correct answer.

"Malevolent" is an adjective that means "having or showing a wish to do evil to others," so we need to pick out a word that means something like "wanting to do evil to others." While three of the answer choices begin with the negative prefix "mal-," only "malicious," an adjective that means "characterized by malice; intending or intended to do harm," is close in meaning to "malevolent." Because "malicious" is the answer choice that is closest in meaning to "malevolent," "malicious" is the correct answer.

"Congenial" and "congenital" are etymologically related but have quite different meanings. "Congenital" means present from birth (if you chose "inherited," you were likely thinking of this word). "Congenial" means agreeable and pleasant to be around. Both words combine the roots "com-" (meaning together) and "-gen" (meaning birth), but they take these root combinations in different directions—"congenital" more literally relating to inborn qualities, and "congenial" relating to the kind of relationship "kindred spirits" might have.

The word "immoral" is best recognized by looking at its parts: "im" + "moral." The "im-" is a prefix meaning not. Generally, this prefix is of the form "i-," though it often adds the consonant that starts the base word—as in "immoral." The word "moral" means either dealing with ethical matters or good, as in someone who is actually ethical. An "immoral" person is someone who lacks such good character and therefore might be called "wicked," which is the best option among those provided. Note: do not confuse "immoral" with "immortal," which means not able to die.

Something that is "minuscule" is very small. Therefore, "small" is the correct answer.

"Abnormal" means unusual or out of the ordinary. Therefore, "unusual" is the synonym.