When something is "defective," it does not function as it should. Therefore, a computer keyboard that doesn't have all of its keys could be called "defective," and we could also call a car with a broken engine "defective." Something that is "faulty" is something with problems like this. The word "faulty" does not have to do with personal faults but with general problems or "faults," as when something does not function properly.

A blemish is a kind of ugly mark on something, as when someone has a pimple on his or her skin.  Indeed, we will sometimes call such pimples "blemishes." Whenever something is said to be "unblemished" it is like someone who has no imperfection on his or her skin. He or she is perfect—at least as regards the skin. In general, "unblemished" can mean "perfect" or "without any imperfection." The word "immaculate" means just this. The root "-maculate," means "blemished." The "im-" prefix is the not prefix. Hence, "immaculate" means not blemished.

"Fleeting" means temporary or short-lived, so "short-lived" is the correct answer. None of the other answer choices are close in meaning to "fleeting": "blissful" means very happy or joyful; "celestial" means related to the sky or the heavens; "plentiful" means abundant; and "filthy" means very dirty or disgusting.

Something that is "abrupt" is sudden or unexpected, so "unexpected" is the correct answer.

Something that is "spontaneous" is not planned; happens by chance or accident. To provide further guidance, "recorded" means written down or preserved. 

"Punctual" means prompt or on time. Therefore, "prompt" is the proper synonym. 

"Eternal" means not having an end or lasting forever, so "never-ending" is the correct answer. None of the other answer choices are close in meaning to "eternal": "illiterate" means not having learned to read or write; "jubilant" means extremely happy and joyful; "passive"  means not active; and "pious" means very religious.

"Arbitrary" means unreasonable or undetermined. "Inconsistent" is the best choice because it means contradictory or erratic. When something is "inconsistent," it is constantly changing and therefore cannot be determined. Considering the other choices, "surprised" means shocked or astonished, "jaded" means worn out, and "unruly" means difficult to control.

Something that is "brisk" is best summarized as quick or fast; for example, a "brisk" wind is one that is blustering.  In terms of the other answer choices, "forlorn" means lonely; "steady" means constant; "leisurely" means laidback; and "fierce" means strong or aggressive.

“Constant” means not changing, staying the same. To provide further help, “fallible” means imperfect; “ghastly” means ghost-like or horrific; “contiguous” means sequential; “sustainable” means able to be kept going.