It is hard for us to imagine today how utterly dierent the world of

1. The primary purpose of this passage is to

(A) compare and contrast nighttime in the modern world with the dark nights of centuries past
(B) explain why the invention of the electric light was essential to increasing worker productivity
(C) lament the loss of the dark nights and the danger and excitement that moonless nights would bring
(D) describe the diminishing brightness of the moon and the subsequent need for more electric lights
(E) argue for an end to the excessive light pollution that plagues 97 percent of the U.S. population

The best way to get an idea about purpose and main point is often to just glance at the first few words of each paragraph to get clues for transitions that introduce each new paragraph.
First paragraph: It is hard for us to imagine today how utterly different the world of night used to be from the daylight world.
Second paragraph: “As different as night and day,” we say today. But in centuries past
Third paragraph: Nowadays

That's a lot of clues that our answer should deal with nowadays compared/contrasted with centuries past.
(A) Wow, that sounds good.
(B) Passage never mentions worker productivity. Incorrect.
(C) "Danger and excitement?" Nope. Incorrect.
(D) No mention of the moon diminishing in brightness. Incorrect.
(E) Doesn't argue anything. Incorrect.

(A) is the only one that addresses nowadays compared/contrasted with centuries past.



2. When the author says, “Many city-dwellers live their entire lives under the equivalent of a full moon,” he is essentially saying that

(A) city-dwellers will never be able to truly appreciate the mystique and beauty of a truly dark night
(B) there is no longer a need for moonlight because artificial light is sufficient
(C) city-dwellers are missing out on much of the beauty of the natural world
(D) the amount of artificial light that shines in cities is enough to produce the same amount of light as a full moon
(E) it is easier to view the moon from cities than from rural areas

(A) "Mystique and beauty" goes too far. Passage doesn't make these qualitative claims. Incorrect.
(B) The quoted text isn't about need for moonlight; it's about presence of artificial light. Incorrect.
(C) See above about (A). Also, no point of view about "missing out." Incorrect.
(D) Almost exactly what the quote says.
(E) Huh? Incorrect.

Answer choice D is the clear winner.


3. The passage mentions all the following as possible ways for travelers to find the path at night except

(A) piles of light-colored stones
(B) the moon
(C) a torch
(D) railings made of light wood
(E) trees with the bark stripped off

(A) Paragraph 2, line 4. Incorrect.
(B) P2, L 5-6. Incorrect.
(C) P2, L7. Incorrect.
(D) Not cited. Correct.
(E) P2, L4. Incorrect.

Answer choice D is the only one not cited.


4. The author includes the statistic “97 percent of the U.S. population lives under a night sky at least as bright as it was on a half-moon night in ancient times” to primarily emphasize which of the following points?

(A) Modern humans have the luxury of being able to see well at night despite cloud cover or a moonless night.
(B) Most modern people cannot really understand how important the moon was to people in centuries past.
(C) Americans are unique among the people of the world in having so much artificial light at night.
(D) A full moon in ancient times was brighter than modern electric lights, which are only as bright as a half-moon.
(E) Light pollution is one of the most important problems facing the United States in the 21st century.

(A) "Luxury" might be a bit strong, but "nowadays we don't need" and "electric lights do it for us" are at least pretty close. Keep it.
(B) Passage never makes this claim. Incorrect.
(C) Passage never makes this claim. Incorrect.
(D) Refuted by the last sentence of the passage. Incorrect.
(E) Passage never discusses light pollution as a "problem," and certainly doesn't rank it relative to other problems. Incorrect.

Answer choice A is the best.