Generally it takes Tule geese about four days to migrate south for the winter. From their summer breeding grounds in...
GMAT Craft and Structure : (Structure) Questions
Generally it takes Tule geese about four days to migrate south for the winter. From their summer breeding grounds in Cook Inlet, Alaska, the birds begin by flying over the Gulf of Alaska, keeping about 100 miles from the Canadian shore. They pause to rest on the Pacific Ocean, then fly toward Summer Lake, Oregon, before finally arriving at their winter destination of Sacramento Valley, California. In 2020, however, it took the geese over twice as long to make their way from Cook Inlet to Sacramento Valley. According to researchers, the reason was airborne pollutants.
Which choice best states the function of the underlined portion in the text as a whole?
It illustrates a change in Tule geese's usual flight behavior.
It suggests an explanation for why Tule geese breed in Alaska.
It describes part of the Tule geese's typical winter migration journey.
It compares Tule geese to other birds that migrate south for the winter.
Step 1: Decode and Map the Passage
Create Passage Analysis Table
| Text from Passage | Analysis |
|---|---|
| 'Generally it takes Tule geese about four days to migrate south for the winter.' |
|
| 'From their summer breeding grounds in Cook Inlet, Alaska, the birds begin by flying over the Gulf of Alaska, keeping about 100 miles from the Canadian shore.' |
|
| 'They pause to rest on the Pacific Ocean, then fly toward Summer Lake, Oregon, before finally arriving at their winter destination of Sacramento Valley, California.' |
|
| 'In 2020, however, it took the geese over twice as long to make their way from Cook Inlet to Sacramento Valley.' |
|
| 'According to researchers, the reason was airborne pollutants.' |
|
Provide Passage Architecture & Core Elements
Main Point: Tule geese normally complete their migration in four days following a specific route, but in 2020 took over twice as long due to airborne pollutants.
Argument Flow: The passage establishes the normal migration pattern with detailed route information, then contrasts this with an exceptional year where the same journey took much longer, finally providing the scientific explanation for this deviation.
Step 2: Interpret the Question Precisely
What's being asked? The question asks about the function of an underlined portion within the text as a whole. Looking at the answer choices, we can deduce that the underlined portion is the detailed description of the migration route (the two sentences describing their journey from Alaska to California).
What type of answer do we need? We need to identify what role this specific portion plays in the overall passage structure.
Any limiting keywords? The question focuses on 'function' which means we need to understand how this portion serves the passage's overall purpose.
Step 3: Prethink the Answer
- The underlined portion gives us the specific details of where the geese go and in what order during their normal migration
- It's not about the 2020 exception - it's about their typical pattern
- The passage structure shows this detailed route description is setting up what normal looks like before contrasting it with the unusual 2020 experience
- The right answer should recognize that this portion describes the standard migration route that these geese typically follow
It illustrates a change in Tule geese's usual flight behavior.
✗ Incorrect
- Claims the underlined portion shows a change in behavior
- The underlined portion describes their normal, typical route - not any change
- The change happens later in 2020, but that's separate from the underlined portion
It suggests an explanation for why Tule geese breed in Alaska.
✗ Incorrect
- Says it suggests an explanation for why they breed in Alaska
- The underlined portion doesn't explain breeding location at all
- It simply describes their migration route, taking Alaska as a given starting point
It describes part of the Tule geese's typical winter migration journey.
✓ Correct
- Accurately identifies this as describing part of the Tule geese's typical winter migration journey
- Matches exactly what we see - detailed description of their normal route
- Typical aligns with the passage's generally timeframe
It compares Tule geese to other birds that migrate south for the winter.
✗ Incorrect
- Claims it compares Tule geese to other birds
- No other birds are mentioned anywhere in the underlined portion
- The passage focuses exclusively on Tule geese throughout