11/6/25
Thousands of years ago, two microscopic spores spawned and created a monster. It grew — up to three feet a year — sending out dark, gnarly, threadlike organs called rhizomorphs that explored the subterranean darkness, foraging for food. Now it’s a nebulous body, a tangled mat beneath the Oregon soil that occupies an area the size of three Central Parks and may weigh as much as 5,000 African elephants.
Its scientific name is Armillaria ostoyae, but you can call it The Humongous Fungus. It’s the largest known terrestrial organism on the planet, according to the United States Forest Service. It’s also a deadly forest pathogen.
Although none (that we know of) are as big, there are many others in the Armillaria genus. These fungi cause root rot disease in plants in forests, parks, orchards and vineyards across North America, Europe and Asia. What sets them apart from other fungi is those stringy rhizomorphs that find weak trees, colonize their roots, kill and eat them.
The passage indicates that “stringy rhizomorphs” are
A. beneficial to trees and other plants.
B. unique to members of the Armilliaria genus.
C. a common characteristic of fungi.
D. destroyed by exposure to light.
The answer is located in the last sentence. The key is to recognize that the word them in the phrase What sets them apart from other fungi is those stringy rhizomorphs… refers to fungi in the Armillaria genus. By definition, something that sets Armillaria fungi “apart” is unique to those fungi. That makes the answer (B).
(A) in incorrect because the passage indicates that Armillaria fungi are highly destructive to plants. (C) states exactly the opposite of what the passage indicates: string rhizomorphs are found only in the Armillaria genus; they are not a “common” characteristic of fungi. Be careful with (D): the passage only states that Armillaria ostoyae spreads in the dark — you cannot make a leap to infer that rhizomorphs are destroyed by light.
11/5/25
For years, seismologists have been trying to identify microquakes. Earthquakes so tiny they don’t even register on traditional measurement tools. Identifying microquakes can help scientists understand earthquake behavior and help them predict dangerous seismic events.
A. NO CHANGE
B. microquakes; earthquakes
C. microquakes, earthquakes
D. microquakes, and earthquakes
Shortcut: period = semicolon = comma + and. Since (A), (B), and (D) are grammatically identical, none of them can be correct. That leaves (C), which correctly uses a colon to introduce the definition of microquakes. Note that while a colon must be preceded by a complete, standalone sentence (For years, seismologists have been trying to identify microquakes), it can be followed by a fragment (Earthquakes so tiny they don’t even register on traditional measurement tools). In contrast, a period, semicolon, and comma + and can only be used to separate two complete sentences.
11/4/25
Self-portraiture isn’t just a byproduct of the smart phone. Since as early as the fifteenth century, artists across different mediums use self-portraits as a way to meditate on the world around them and their places within it. More than just capturing physical features, these images allow artists to channel their beliefs into their work in ways that are both revealing and revolutionary.
A. NO CHANGE
B. used
C. have used
D. had used
The word since, which appears at the beginning of the sentence, is a tip-off that the present perfect (have used) is required. This tense indicates that an action began in the past (fifteenth century) and is continuing into the present. Only (C) provides this tense, so it is correct.
11/3/25
The strings of letters that make up genes are largely useless on their own; instead, like blueprints for the many proteins in the body. To actually build something, or be expressed, certain genes must be switched on. Spaceflight seems to affect the level of this expression for some genes—especially those that play a role in the immune system, DNA repair, and bone growth.
A. NO CHANGE
B. own, instead like blueprints,
C. own. Instead, they are like blueprints
D. own instead being like blueprints
(A) is incorrect because a semicolon can only separate two sentences, and instead, like blueprints for the many proteins in the body is not a sentence. (B) is incorrect because the two commas signal a non-essential phrase; however, the sentence no longer makes sense when the information is removed (The strings of letters that make up genes are largely useless on their own…for the many proteins in the body). (D) is incorrect because some form of punctuation is required before instead to signal the start of a new clause. In addition, the word being reliably signals a wrong answer. (C) is correct because it adds a subject and verb (they are) to the second clause and uses a period to separate the resulting two sentences.
11/2/25
In some form or another, doughnuts have existed for so long that archaeologists keep turning up what look like fossilized bits of them in the middle of prehistoric settlements. But the doughnut proper, (if that’s the right word), supposedly came to Manhattan, then still New Amsterdam, under the unappetizing Dutch name of olykoeks—“oily cakes.”
A. NO CHANGE
B. proper, (if that’s the right word)
C. proper (if that’s the right word),
D. proper (if that’s the right word)
As a general rule, a non-essential clause can be set off by either commas or parentheses but not both. In rare cases, when a comma is necessary for other reasons, one may be placed after a close-parenthesis, but a comma before an open-parenthesis, or before and after a set of parentheses, is always incorrect. That automatically eliminates (A) and (B). Because there is no grammatical reason to place a comma after the close-parenthesis here, no commas are necessary, making the answer (D).
11/1/25
For cost-conscious clothing shoppers in 1920, it must have seemed like a miracle: men’s suits in a choice of 50 different styles for a mere 60 cents each (about $7.66 today). What’s more, when a suit got dirty, you could easily clean it—with an eraser. The first rubber erasers had been produced in England more than a century earlier. Paper clothing had arrived, largely imported from Germany and Austria, where World War I shortages of wool and other materials had spurred its development.
The writer is considering deleting the underlined information. Should the writer do this?
A. Yes, because the passage does not state that rubber erasers could be used to clean the suits.
B. Yes, because the passage focuses primarily on paper clothing.
C. No, because the passage indicates that paper clothing was erasable.
D. No, because the passage states that the suits seemed like a miracle.
“Delete” questions are essentially asking you one thing: whether the information in question is on- or off-topic. As a result, you must start by identifying the topic of the passage. What is the topic? Paper clothing (suits). What is the sentence in question about? The first rubber erasers? Is that the same thing as paper clothing? No, so the sentence should be deleted. Why? Because it’s off-topic (i.e., not about paper clothing). That makes the answer (B).
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