The correct answer is "danger," because both "threat" and "danger" mean something that can potentially harm someone. "Safety" is an opposite of "danger," and the other two words do not have to do with "threat."

"Fiasco" is another word for an event that fails in a disastrous way. You might call your birthday party a fiasco if it rains all day, everyone gets lost on the way to your house, and the ice cream melts—in other words, if everything goes wrong. So, "disaster" is the word that we're looking for here. "Success" implies that the event went well, and both "boredom" and "numbness" imply a lack of interest or feeling about the situation.

A "collision" is the event of one object hitting another, or a "crash." An "achievement" is an accomplishment or the completion of some task or goal. "Reign," when used as a noun, means the period when a person rules or governs. "Homonym" refers to a word that is pronounced in the same way as another word, but has a different meaning than that other word. A "route" is a path or road.

A "harbinger" is something or someone that is a sign of a future event. The best choice is "omen," which shares the same definition. Considering the other choices, "chaos" means a state of utter confusion, "auxiliary" means additional, and "guard" means a person that protects someone or something.

A "harbinger" is something that foretells that something else is approaching. "Omen" is the best match because it means a warning about something that will happen in the future.

A "truce" is an agreement reached after a conflict by each person or group involved in it not to continue fighting. None of the other answer choices are close in meaning to "truce": "resentment" means indignation or bitterness; "disapproval" means displeasure or criticism; and "opposition" means objection or resistance.

A "chapter" is a section of a book.

"Donation" is a noun that means "something that is given to a charity, especially a sum of money." So, we need to pick out an answer choice that means something like "something that is given to a charity." "Price," then, cannot be the correct answer, because while "price" can refer to a sum of money, it specifically means "the amount of money expected, required, or given in payment for something," not "something that is given to a charity." "Contribution," however, is a noun that means "a gift or payment to a common fund or collection," and because "contribution" is the answer choice closest in meaning to "donation," "contribution" is the correct answer.

"Precipice" is a noun that means "a very steep rock face or cliff, typically a tall one," so we need to pick out an answer that means something like "a very steep rock face." Both "landform" and "peak" might look like potentially correct answers, "peak" means "the pointed top of a mountain" or "a mountain, especially one with a pointed top," neither of which mean "a very steep rock face or cliff," and while a "precipice" may be a type of "landform" ("a natural feature of the earth's surface"), "precipice" does not mean the same thing as "landform." "Cliff face," however, is synonymous with "precipice," and because "cliff face" is the answer choice closest in meaning to "precipice," "cliff face" is the correct answer.

"Debt" means loan.