Question 110·Medium·Rhetorical Synthesis
While researching a topic, a student has taken the following notes:
• Roman builders mixed volcanic ash, lime, and seawater to create an especially durable concrete.
• Structures made with this material—such as the Pantheon dome and ancient harbor piers—have endured for more than 1,900 years.
• Modern concrete, by contrast, often deteriorates within a few decades when exposed to saltwater.
• Volcanic ash in the Roman mix can trigger autogenous healing, allowing the concrete to fill tiny cracks as they form.
• Engineers are studying the ancient formula to design longer-lasting, more sustainable construction materials.
The student wants to emphasize the striking difference in longevity between Roman concrete and most modern concrete. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For rhetorical synthesis questions like this, first underline the task words in the question (here, “striking difference in longevity”). Then scan the notes and mark only the bullets that directly support that task. Next, eliminate any choices that (1) ignore the key idea, (2) use unrelated notes (like side details about architecture or sustainability), or (3) mention only one side of a needed comparison. The correct answer will tightly combine the most relevant notes and clearly match the specified purpose without adding extra, off-focus information.
Hints
Focus on the exact goal
Underline the phrase “striking difference in longevity between Roman concrete and most modern concrete.” Which pieces of information from the notes directly describe how long each type of concrete lasts?
Locate the key bullets in the notes
Find the bullet(s) that talk about Roman structures lasting a very long time and the bullet(s) that talk about modern concrete not lasting as long, especially in saltwater.
Match choices to the longevity contrast
Which option uses information about both Roman and modern concrete and clearly shows a contrast in their lifespans, instead of focusing only on ingredients, healing, architecture, or sustainability?
Step-by-step Explanation
Identify the writing goal
The question says the student wants to “emphasize the striking difference in longevity between Roman concrete and most modern concrete.”
So the correct answer must:
- Talk about how long Roman concrete lasts.
- Talk about how long modern concrete lasts.
- Make the difference between them clear and strong (a contrast).
Find the most relevant notes
Look at the notes and ask: which bullets deal with how long the concrete lasts?
- Bullet 2: Roman structures “have endured for more than 1,900 years.” → Roman concrete lasts a very long time.
- Bullet 3: Modern concrete “often deteriorates within a few decades when exposed to saltwater.” → Modern concrete doesn’t last long.
These two bullets together give the striking contrast in longevity that the question wants. The other bullets are about ingredients, healing mechanism, and sustainability, which are less central to the stated goal.
Check which option uses the key contrasting details
Now scan each answer choice and see which one:
- Uses information from both relevant bullets (Roman longevity and modern short life), and
- Clearly contrasts Roman concrete with modern concrete.
Only one choice includes both that modern concrete “succumb[s]…within decades” and that Roman concrete has supported structures for nearly two thousand years, turning those notes into a direct comparison.
Confirm the best match with the goal and notes
The choice that says “Because modern concrete structures frequently succumb to saltwater damage within decades, engineers now study Roman concrete—made from volcanic ash, lime, and seawater—that has supported harbor piers for nearly two millennia.”
- Uses the note about modern concrete deteriorating within decades.
- Uses the note about Roman harbor piers lasting nearly 1,900+ years.
- Directly contrasts the two to emphasize the difference in longevity.
Therefore, this sentence is the best and correct answer.