Question 9·Hard·Rhetorical Synthesis
While researching a topic, a student has taken the following notes:
• Coral bleaching happens when corals expel the symbiotic algae (zooxanthellae) that live in their tissues, causing the corals to turn white.
• Elevated sea-surface temperatures are the primary trigger for bleaching events.
• Because the algae supply much of the corals’ energy, their loss weakens the corals.
• Prolonged bleaching can kill corals and lead to the decline of entire reef ecosystems.
The student wants to write one sentence that explains both the cause and the potential consequences of coral bleaching. Which choice most effectively uses relevant information from the notes to accomplish this goal?
For rhetorical synthesis questions like this, first restate the task in your own words (for example, “one sentence that gives both cause and effects”). Then quickly label each note as cause, description, or consequence so you know which ideas must appear together. Go through the answer choices and use a checklist: eliminate any option that is missing a required piece (like the cause) or that focuses on only one detail instead of synthesizing multiple notes. Prefer the choice that accurately combines the key points from several notes into a single clear sentence without adding unsupported information.
Hints
Clarify what the sentence must do
Underline the words in the question that describe the task: the sentence must explain both the cause and the potential consequences of coral bleaching. Any choice that does only one of these is not enough.
Match notes to “cause” and “consequences”
Look back at the notes and decide which bullets describe what starts bleaching and which describe what happens to corals and reefs afterward. Keep those ideas in mind as a checklist.
Test each choice against your checklist
For each answer, ask: Does it clearly say what triggers coral bleaching and also describe what might happen to corals or reefs if bleaching continues? Eliminate choices that are missing either part or that only mention a narrow part of the consequences.
Step-by-step Explanation
Understand the writing task
The question asks for one sentence that explains both:
- the cause of coral bleaching, and
- the potential consequences of coral bleaching.
So the correct answer must clearly include what starts bleaching and what might happen because of it.
Sort the notes into cause vs. consequences
Look at each bullet in the notes and decide whether it describes cause, description, or consequence:
- “Coral bleaching happens when corals expel the symbiotic algae … causing the corals to turn white.” → what bleaching is / how it happens.
- “Elevated sea-surface temperatures are the primary trigger for bleaching events.” → the cause.
- “Because the algae supply much of the corals’ energy, their loss weakens the corals.” → an immediate consequence.
- “Prolonged bleaching can kill corals and lead to the decline of entire reef ecosystems.” → more serious, longer-term consequences.
The best sentence will combine the trigger (elevated temperatures causing corals to expel algae) with the effects (weakened corals and possible reef decline).
Use the task to eliminate incomplete choices
Now compare each choice to what the question requires:
- Cross out any choice that only tells you what causes bleaching but does not mention what happens afterward.
- Cross out any choice that only tells you about damage to reefs but does not say what triggers bleaching.
- Be careful of choices that mention only one part of the consequences (for example, just that corals may die) instead of the broader impact on coral and reef ecosystems.
Only a sentence that includes both a cause and a clear description of the possible chain of effects matches the task.
Identify the option that fully matches notes and task
When you check the answer choices with this in mind, only one sentence does everything required: it defines bleaching as corals expelling symbiotic algae, states that this is usually triggered by elevated sea-surface temperatures, and then explains that losing algae-derived energy weakens corals and, if bleaching continues, can lead to the decline of entire reef ecosystems. That sentence is:
D) Coral bleaching occurs when corals expel the symbiotic algae living in their tissues, a stress response most often triggered by elevated sea-surface temperatures, and the resulting loss of algae-derived energy weakens corals and, if bleaching persists, can lead to the decline of entire reef ecosystems.