Likely, knowledge of the word "quip" is a matter of vocabulary. Its roots are rarely used in other words. In general a quip is a witty joke. The word can also be used as a verb to indicate the act of making such a joke. Thus, the best option among those given is the simple word "joke."

The word "terminal" comes from the Latin word "terminus," meaning end or limit. At the airport, the "terminals" are the corridors at which fliers catch their planes. They are called "terminals" precisely because they are on the ends of the main buildings, thus being approachable by incoming and outgoing planes. A "terminal illness" is an illness that is likely to be fatal. It is one that will lead to the terminus of life—that is, to the end of life. Thus, among the options provided, the best option is "final." Something that is "terminal" is final. Do not be tricked into thinking that "ill" or "medicinal" are correct just because of their relation to health issues. That is not the same as being a terminal illness.

The word "archaic" describes something that is very ancient. Often, this also implies that the given thing is out of date. The word "obsolete" best describes something of this sort. Do not be tricked by "historical". Things that are not very ancient can still be historical. Likewise, something archaic might be tedious to deal with, but this is not necessarily the case. 

"Intermittent" means sporadic, occurring randomly and infrequently. To provide further help, "fastidious" means obsessive and hard to please; "exhaustive" means comprehensive; "frequent" means occurring regularly; "torpid" means lethargic, lacking energy. 

"Expedient" when used as an adjective means convenient, advantageous. When used as a noun it means a means of achieving something, a scheme. To provide further help, "reticent" means reluctant to share, withdrawn; "truculent" means aggressive; "ebullient" means enthusiastic; "incumbent," when used as an adjective, means required, obligatory. "Incumbent" can also be used as a noun in which case it means person who already holds the office or title. 

Privy means to be in on or sharing some secret knowledge, or informed.

The word “spurious” most generally means false or fake, often implying that the fake thing does not at first appear to be fake, though it really is. Often, one will find the word used to describe a “spurious argument” or a “spurious claim,” meaning arguments and claims that are ultimately false.

"Demonstrative" is an adjective that can mean openly demonstrating feelings or providing conclusive proof. We need to pick out an adjective that means something like showing feelings or providing proof. "Inconclusive" cannot be the correct answer because it is an antonym of the second meaning of "demonstrative," providing conclusive proof. "Indisputable," however, is an adjective that means unable to be disputed and because it is the answer choice closest in meaning to "demonstrative," "indisputable" is the correct answer.

Affected means artificial or pretentious.

When used as an adjective, the word “dubious” means “doubting” or “hesitating.” It is clearly related to “dubious” as well as the word “indubitable,” which means “unable to be doubted.” It would be used in a sentence like, “Since the argument presented to him was rather weak, John remained rather dubious regarding the truth of its conclusions.” Among the options provided, “uncertain” is the closest to this sense.