"Inevitable" means unable to be avoided or definitely bound to happen. "Unavoidable" is therefore the word choice that matches the definition. "Unpredictable," "unpleasant," and "incredible" are all unrelated to the definition. 

"Timely" is defined as done or occurring at a favorable or useful time. The best answer choice is "convenient," which means fitting in well with a person's schedule.

When something is rapid, it moves quickly. Although this kind of movement might make for a "short time" or a "tiny amount of time," these kinds of expressions are not quite correct as synonyms. The word "rapid" has to deal with swiftness of speed. Thus, the word "quick" is the best option among those given.

You almost certainly know that the movement of a snake is called "slithering." While this kind of movement is not "crawling" in the way that a human baby crawls, it is a slow movement that is very close to the ground. For this reason, "crawl" can be an acceptable synonym. Since there are no better options, this is the correct choice for this question.

When we describe someone's action as being "prompt," we are saying that it is speedy or quick. Perhaps you have heard your parents say that the service at a restaurant or store is "prompt." This means that it is quick and without delay. The word "rapid" means "quick," so it is the best option for a synonym.

Whenever something is temporary, it exists only for a limited amount of time.  For example, if there is a temporary increase of school work, this means that the work is only going to be increased for a limited period of time.  Another example of something "temporary" would be a particular food item that is only available during a particular time of the year.  It is only available temporarily.  Such things are only around for a brief time, so the adverb "briefly" is a good synonym.

Conventional means traditional, normal, or usual. To further help you, the other four answer choices are all antonyms of conventional because they have the opposite meaning. Abnormal means not normal; absurd, bizarre and ridiculous all mean very weird. 

"Affiliated" means connected to or partnered with. To further help, you, the "protagonist" is the hero of the story; the "antagonist" is the villain of the story; "narrator" means storyteller. 

"Distant" means far away or aloof. To further help you, "blend" means mix together or combine; "separate" means not connected or not combined when used as an adjective and pull apart when used as a verb. "Separate" is an antonym of "combine" and "blend."

"Barren" means empty, devoid of life, or when referring to a woman, unable to have children. So, "empty" is the correct answer. None of the other answer choices are close in meaning to "barren": "fecund," "fertile," and "abundant" are synonyms which all mean plentiful or producing a lot of life, so "barren" is an antonym of "fecund," "fertile," and "abundant."