In saying that "no metals, other than the expensive, nonoxidizing gold, could be relied upon to give off positive-lig...

Ravi on January 16, 2019

@Boram,

Happy to help. When the author says, "No metals, other than the
expensive, nonoxidizing gold, could be relied upon to give off
positive-light reflections," the author is making a distinction
between gold and other metals. You're right about that.

But what is the distinction? The key word in this phrase is
"nonoxidizing." Even if we don't know what this means, the passage
provides context that allows us to figure out this term's meaning.

First off, the last portion of the phrase in question tells us that
gold, unlike the other metals, could be relied upon. That 's the first
clue of what "nonoxidizing" means. We then are told about Noguchi's
wishes in the next paragraph, as he wanted to make a purely reflective
sculpture. At the end of the paragraph when discussing chrome-nickel
steel, the author states, "Here, finally, was a permanently reflective
surface, economically available in massive quantities."

From this, we can infer that the nonoxidizing properties of gold were
preferred by Noguchi because it somehow made gold more reliable,
purely reflective, and permanently reflective.

In the answer choices, we're looking for an answer that touches upon
gold's ability to be more reliable, purely reflective, and permanently
reflective than its other metal counterparts. Gold is preferred
because it's long lasting and will remain reflective over time.

Answer A is incorrect because it's not the direction we care about.
We're primarily concerned with gold's ability to be permanently
reflective (long lasting), and this answer doesn't touch upon that
distinction. We can get rid of this choice.

Answer B is incorrect because it fails to mention the key distinction
of gold having greater reliability and permanence than its other metal
counterparts. We can eliminate this choice.

Answer C is correct; it properly captures the distinction the author
is referring to because it describes metals that lose their reflective
properties over time and a metal that does not lose its reflective
properties over time. This is exactly why gold was better than the
other metals—it was reliable and permanently reflective. This is our
answer choice.

Answer D is incorrect because it inaccurately states that the author
is drawing a distinction between metal and nonmetallic materials. The
author is comparing one type of metal (gold) with other types of
metals.

Answer E is incorrect because the distinction is not between highly
reflective metals that were acceptable vs. experimental; rather, the
distinction is between gold and its greater reliability and reflective
permanence when compared to other metals.

Does this make sense? Let us know if you have any more questions!