The prefix "contra-" or "contr-" generally means against. "Contra dancing" is a kind of dancing in two lines that face each other, and "counterpoint" is a kind of music that has two musical lines that run "against" each other, weaving together melodies and harmonies. When someone is "contrary," he or she acts in a way that is always against other people's opinions. He or she generally is a troublesome personality and is thus someone who is uncooperative. Thus, we are looking for a descriptive word for "senile." While we often use this word to describe people who are losing their memories, the word can describe the more general condition of someone who is becoming aged. Someone who is senile is becoming infirm and weak with age. The word "senator" comes from a similar root, meaning old man.

The word "illustrious" comes from the Latin root meaning clear or bright.  Having a "luster" is to have a glow or a shine, and an "illustration" is something that makes its topic clear by means of a kind of example. Someone who is selfish thinks of himself or herself. This is the meaning of "ego-centric," which literally means "I-centered." We are therefore looking for a synonym of "illustrious." Generally speaking, this word means well-known—as though a bright light is visible. Such a person or thing would also be "eminent."

The "topography" of an area pertains to the physical character of that area—its hills, valleys, rivers, and so forth. The word comes from Greek roots that generally mean "place" (topos) and "drawing" (graphia). A map records an area's topography. A timeline records the ordering of occurrences. While this could be historical in nature, it could even be a timeline of scientific facts. The best option is therefore "chronology," which indicates an ordered set of events based on when those events occurred. It comes from the Greek for "time," kronos.

A tassel is placed at the end of a cord, generally as an ornament. (It is the little “stringy tuft” at the end of such cords). A “valediction” is a statement of farewell. The “valedictorian” of a class is so named because he is the one who says “farewell” on behalf of the class. (Also, he speaks after the salutatorian, who is the one who greets the class. The word “salutatorian” comes from words in Latin used to greet someone). Thus, among the options provided, the only proper case is “conversation,” for a “valediction” comes at the end of a conversation as a tassel comes at the end of a cord.

A novice is a person who is inexperienced or new to a given field of study or work. Thus, such a person is at the beginning of his or her work in that area. A “terminal” is something that is at the end of a structure or process. A terminal does necessarily occur only at the “finish line” (so to speak), as both ends of a (e.g.) stick can be considered its “terminal points.” Still, just as a novice is metaphorically at the beginning of his or her work, so is a terminal point (physically or metaphorically) at an end of a process or physical being. Since no other option captures this sense of “location” (whether physically or metaphorically), “end” is the best option for this analogy.

A "septagon" has "seven" sides, just as a "nonagon" has "nine" sides.

The word “pulmonary” comes from the Latin word for the lungs. It is used to in English to describe physical conditions related to these organs, as when someone has pulmonary embolism, which is a type of blockage of blood to the lung. Just as “pulmonary” describes the lungs, “cardiac” describes conditions related to the heart.

"Primary" and "first" are synonyms, just as "tertiary" and "third" mean the same thing.

A "guitar" and a "lute" are both stringed instruments, just as a "clarinet" and an "oboe" are both woodwind instruments. 

A syllable is a component of a word, a single unit of sound. We say that words are comprised of a number of syllables; therefore, we could write a bridge sentence like, “Just as a syllable is part of a word, so is a buckle part of a X.” While a buckle could be said to latch, snap, fasten, or secure, it is a part of none of these words. It is a part of a belt, which is a whole thing that has a buckle on it; therefore, this is the best option among those provided.