The Latin prefix avia- means bird, as in "aviary" which is a place where birds are kept. So, this problem is a little more confusing than usual, but can still be solved using logic. An "aviator" must have something in common with a "bird," well an "aviator" is a pilot. Pilots and birds can both fly. This happens sometimes with the English language due to the complexity of the origin of some words, but more often than not you can determine the meaning of words using logic and an understanding of prefixes, suffixes, and roots of words. 

The Latin prefix sub- means under, beneath, as in "submerge" which means to go under water. So, "substandard" means below standard, not good enough, of poor quality. Additionally, "grand" means impressive, magnificent, great; "jaunty" means cheerful, having a good-natured personality. 

The Latin prefix capt- means take, hold, as in "capture" or "intercept." So, a "captive" is someone who is being held against their will, someone who has been taken, a prisoner. "Secretary," "assistant," and "guard" are all jobs. "Learner" is a person who enjoys and is good at learning.

The Latin prefix grat- means please, pleasing. So, "gratifying" means pleasing, pleasurable, something that makes someone feel good about themselves or happy. To provide additional help, "deceiving" means tricking; "maddening" means something that makes someone angry, frustrating and annoying.

The Latin prefix per- means through, throughout, so "permeate" means to spread throughout something. Other examples of per- words are "pervade" which also means to spread throughout and "permanent," which means lasting throughout all time.

"Inconsequential" means not important, therefore "unimportant" is closest in meaning to "inconsequential."

The prefix of the word "converge" is "con-", which is a form of the general prefix for "with" or "together," namely "con- / cum- / com- / etc."  Whenever things "converge," they come together into a group. For example, you could say, "The people converged on the small town, overwhelming it with their great numbers." This means that the people all came together in the small town.

Only the option "unite" expresses the idea of coming together or of being one group.

The word "commemorate" comes from Latin roots meaning roughly to remember together. The "com-" prefix is a form of "cum-" or "con-" that we find in words like "community," "cumulative," and "congregation." It means together or with. When we commemorate something or someone, we remember that person or thing together as a group. In doing this, we honor that which we commemorate. Think of annual ceremonies that commemorate events like September 11, 2001 (to honor its victims) or the signing of the U.S. Declaration of Independence.

Whenever we "intend" something, we actively will to do that thing. An intentional action is one that doesn't "just happen", as when we accidentally have our hands slip from a surface because it is slippery. In contrast, an intentional action is something chosen. Thus, when something is "intended," it was "meant"; that is, you can say either, "I intended to do that," or, "I meant to do that."

Among the options provided, only "premeditated" expresses this idea of meaning to do an action. The word "pre-meditated" contains hints regarding its meaning. The suffix "pre-" almost always means before. The idea of "meditation" in this word is not about the practice of religious or non-religious meditation but, instead, about thinking in general. A premeditated action is one that we planned ahead of time. We think about these things before we do them; we "pre-meditate" about them. This is close to "intending," at least for the purposes of this question.

The word "antecedent" may be a bit difficult; however, let's use some roots to help understand it. The prefix "ante-" means before. In certain card games, people will place a bet before they even receive any cards and know what their hand is or will be. This kind of bet is called "ante." Similarly, when we talk about the southern states of the United States from before the U.S. Civil War, we refer to the "antebellum" South. The "bellum" portion means war. Therefore, "antebellum" means before the war.

Now, the second half of "antecedent" comes from Latin roots meaning to fall. It is related to the word "cadence," which refers to the beat in music or the pitch of someone's voice (how it rises and falls, so to speak).

Thus, after a long digression, we have the meaning of "antecedent": it means to fall before. Hence, "prior" is an excellent option!