"Toxic" is an adjective that means "causing or capable of causing death or illness if taken into the body" when used of a plant or substance, "producing poison as a means of attacking enemies or prey" when describing an animal or insect, or "extremely unpleasant or malicious." While "fulsome" might look like a good answer choice, "fulsome" actually means "complimentary or flattering to an excessive degree" or "of large size or quantity; generous or abundant," so it cannot be the correct answer. "Poisonous" however, is a synonym of "toxic," so "poisonous" is the correct answer.

"Turbulent" means characterised by agitation or chaos. "Tempestuous" means stormy, so it is a synonym of "turbulent." "Calm," "tranquil" and "peaceful" are all antonyms of turbulent that mean untroubled.

"Wanton" can mean random, so "random" is the correct answer. To help you, "implausible" means almost impossible or hard to believe, "credible" means reliable, "demeaning" means humiliating or undignified, and "suspicious" means doubtful.

The word "virulent" means harmful. "Harmful" is the best choice, as it is a part of the definition of "virulent."

The word "auspicious" means promising success. The best choice is "promising," as it shares the same definition as "auspicious." Considering the other choices, "austere" means strict, "oust" means overthrow or remove from a position, and "howl" means cry out.

"Prone" means to be inclined towards doing something. For example, if you are "prone" to lying, then you lie often. To further help you, "cautious" means careful and wary; "objective" means subject to logic instead of personal opinion; "subjective" is an antonym of "objective" and means subject to personal opinion instead of logic.

"Auspicious" means fortunate, promising, favorable; a lucky start or omen. To provide further help, "audible" means able to be heard; "carnage" refers to large scale slaughter and pillaging; "mayhem" means chaos; "potential" means the possible ability of something.

Someone who is “destitute” is broke and penniless. To provide further guidance, "ostentatious" means defined by luxury and wealth; "comely" means cute; "ominous" and "menacing" are synonyms that both mean threatening, suggesting that danger is imminent. 

The word “prone” means likely to suffer from something specific. This is closest in meaning to “susceptible,” which means at risk from something specific. To provide further help, “wily” and “cunning” are synonyms that both describe someone who is smart and tricky, someone with lots of guile. Additionally, “portly” means fat and “comely” means cute. 

The word "capable" comes from the Latin meaning able to take in. If you look at its roots, it is like "able to capture." Someone who is described as being "capable" is able to "take in and accomplish a task." This person has a certain ability and could be said to be "effective," which means able to bring something about. The options "handy" and "educated" are tempting, though they are not necessarily synonyms. A capable person is probably handy, since they can do something. Likewise, being educated can (but not necessarily) lead to capabilities. However, neither of these are as close in meaning to "capable" as is "effective."