Question 161·Medium·Transitions
Extensive surveys of Caribbean coral reefs conducted between 2010 and 2020 confirmed that rising ocean temperatures are the primary driver of coral bleaching events. ______ researchers identified several heat-tolerant strains of symbiotic algae that, when introduced to vulnerable corals in laboratory settings, significantly improved the corals’ survival rates during thermal stress.
Which choice completes the text with the most logical transition?
For transition questions, first read the sentences without the transition and decide the relationship in your own words: is the second idea contrasting, adding, illustrating, explaining a result, or happening later in time? Then, look at the answer choices and quickly label each one by its usual function (contrast, time sequence, example, etc.). Eliminate any choice whose function does not match the relationship you identified from the context, and only then pick from the remaining options—this is much faster and more reliable than trying to “plug in” each choice and going by sound alone.
Hints
Check how the second sentence relates to the first
Ask yourself: Is the second sentence agreeing with, disagreeing with, giving an example of, or simply adding on to the first sentence?
Look for the purpose of the second sentence
The first sentence states a problem (why bleaching happens). The second sentence describes research about algae and survival—how is that connected to the problem identified by the surveys?
Compare the meanings of the answer choices
Think about what each transition usually shows: contrast, things happening at the same time, giving an example, or moving the discussion forward. Which one best matches the relationship you found between the two sentences?
Step-by-step Explanation
Understand what each sentence is doing
First sentence: surveys of Caribbean coral reefs (2010–2020) confirmed that rising ocean temperatures are the main cause of coral bleaching.
Second sentence: researchers then identified heat-tolerant algae strains that, when added to vulnerable corals in labs, helped those corals survive heat stress.
So the second sentence describes new, related research that comes after and builds on the surveys.
Identify the logical relationship between the sentences
Ask: how does the second sentence relate to the first?
- It does not contradict the first sentence; instead, it accepts the problem (heat causes bleaching) and looks for a solution.
- It describes research that follows the surveys and responds to the problem identified.
So the connection is a continuation in time and purpose (follow-up work), not opposition, not an unrelated side note, and not simply an example of the surveys.
Match each option to its typical use
Now connect this relationship to the choices:
- “Nevertheless,” is used when the second idea goes against or in spite of the first.
- “Meanwhile,” is used for something happening at the same time as something else.
- “For example,” introduces a specific instance or illustration of a general point.
- One remaining option is commonly used when one event or action comes after another in a sequence.
Only the option that indicates a later, follow-up action will fit the relationship we found.
Choose the transition that shows a later, follow-up action
The second sentence describes what researchers did after the surveys: they went on to identify heat-tolerant algae and test them in labs. The only transition that clearly shows this “next in time” relationship is “Subsequently,” so the correct answer is C) Subsequently,.