"Adapt" and "adjust" are synonymous. They refer to something changing in order to conform. The other words do not share this meaning.

"Inquire" means to investigate or question. You might "inquire" of your teacher how long the test will take. When used as a verb, "question" also means to ask questions or investigate.

"Motivate" means to encourage someone. This is similar to the word "inspire," but not "inquire."

"Harmonize" is a form of singing where two or more people sing different, complimentary notes.

When you "compete," you work against another person or a group of people in order to win a game or achieve a goal.

The word that has the most similar meaning to CONCLUDE is "finish." To CONCLUDE a discussion, you "finish" it. 

"Include" means make whole, or make part of a set.

Using "film" as a verb means, creating a movie.

"Fancy" is an adjective meaning elaborately decorated.

"Deliberate" means done on purpose.

"Jest" means to joke or make light of a situation. A variation is the word "jester," like a clown. While "joke" can also be used as a noun, it can also be used as a verb, as it is for this synonym. While "jesting" may be accomplished through "talking" the words are not directly related in their definitions. "Cough" is totally unrelated to "jest," and the other answer choices all describe actions with negative connotations, and thus cannot be synonymous with "jest" or "joke."

"Counsel" most nearly means to advise or give explanation. Variations include "counselor", such as a legal advocate or therapist. "Counsel" should not be confused with its homonym "council," which refers to a group of individuals who make collective decisions. "Cooperate" and "forgive" have no relation to the word "counsel."

"Decree" most nearly means to declare or to make a formal declaration. "Decree" can also be used a noun, for example a "royal decree" from a monarch. "Denounce" and "deny" both relate to refusing a fact or circumstance and are therefore not exact synonyms of "decree." "Decide" is somewhat related to the word "decree", as it means to come to a resolution or answer on a question; however, to "decree", that decision must be announced publicly, which more closely related to the word "declare." "Deviate" has no relation to the word "decree."

"Placate" most nearly means to appease or to calm through agreement. The words "pretend," "aspire," "quit," and "convene" have no relation to the word "placate." "Aspire" means to direct one's ambitions towards a goal (for example, "She aspires to be a doctor.") "Convene" most nearly means to bring together in a group.

"Condone" is a verb that means to allow or forgive. A typical example would be an authority figure who "condones" a subordinate's behavior. "Supply" and "forget" have no relation to the word "condone," while "prohibit" and "condemn" are antonyms. Therefore, the correct answer is "allow." 

"Arguing" involves a disagreement between two or more people who hold different views on a topic. "Quarreling" is the best synonym of "arguing."

Incorrect Answers:

"Talking" means to speak.

"Whispering" means to speak quietly.

"Communicating" involves the sharing of information.

"Assisting" means to help someone else.

"Confess" means to accept fault for something. "Acknowledge," which means to admit guilt, is the best synonym of "confess."

Incorrect Answers:

"Yearn" indicates a desire to do something.

"Ponder" means to think about.

"Enable" involves giving someone the power to do something.

"Create" means bring something into existence.