Question 176·200 Super-Hard SAT Reading Questions·Expression of Ideas
A single satellite image can capture the sudden collapse of a glacier’s ice front. ______ to understand how the glacier flows over years, researchers compare long sequences of images taken at regular intervals.
Which choice completes the text with the most logical transition?
For transition questions, always read at least one sentence before and after the blank, then briefly summarize in your own words how the ideas relate: same direction, contrast, cause/effect, example, or concession. Label the relationship first, then check each answer choice’s function (contrast, result, example, etc.) and eliminate any that don’t match that labeled relationship—even if they sound smooth—before selecting the one that clearly matches the logic of the sentences.
Hints
Compare the two sentences’ main ideas
Read both sentences together and ask yourself: Is the second sentence showing a result, giving an example, or contrasting a different way of doing something?
Think about time scale and method
Notice that the first sentence talks about a single image capturing a sudden event, while the second talks about images taken over years. What kind of relationship does this suggest?
Match meaning to transition types
Remember: one choice indicates result, one introduces an example, and two indicate different kinds of contrast. Decide which type of relationship you see, then pick the transition that signals that type.
Step-by-step Explanation
Understand what each sentence is saying
Paraphrase the two sentences:
- First sentence: One satellite photo can show a sudden collapse at the front of a glacier.
- Second sentence: To understand how the glacier moves over many years, researchers look at a long series of images taken regularly. So the first is about a single image capturing a sudden event; the second is about many images revealing long-term movement.
Decide the logical relationship between the sentences
Ask: How does the second idea relate to the first?
- It is not a result of the first; the second describes a different research method.
- It is not an example of the first; it introduces a separate, contrasting use of satellite images (long-term flow vs sudden collapse).
- The two sentences describe two different kinds of information satellite images can provide. That means the relationship is a contrast between a single image and a sequence of images, and between short-term and long-term observation.
Recall what each transition usually signals
Match each option to the kind of relationship it indicates:
- By contrast, → signals a difference between two situations or methods.
- Consequently, → signals a result or effect.
- For example, → introduces a specific instance of a more general idea.
- Nevertheless, → signals a surprising contrast or something that happens despite what was just said. We want the one that fits a straightforward comparison of two different methods.
Choose the transition that matches a simple contrast
Because the sentences are directly comparing two different uses of satellite images (one image vs many images; sudden collapse vs long-term flow), the transition that clearly signals this difference is “By contrast,” which makes option A) By contrast, the correct answer.