The observer effect that the author is trying to explain is turtles "returning to their birthplaces to nest some 15 to 30 years later."
The proposed cause?
"Newborn sea turtles learn the smell of their birth environment, and it is this smell that stimulates the turtles to return to nest."
So to summarize this stimulus:
Effect = Return to Nest
Cause = Smell
This is an argument evaluation question so we are looking for the answer choice that would help us evaluate this argument.
(D) states, "whether immediately before returning to nest, sea turtles are outside the area where the smell of their birthplace would be perceptible."
If the answer to (D) was true, it would clearly cast doubt on the hypothesis that smell is the cause for their return.
As such, (D) would be the correct answer.
Hope this helps! Please let us know if you have any other questions.
nathaniellim97May 21, 2018
@Mehran, Why is (B-what the maximum migratory range of mature sea turtle is) not the answer to this question?
MehranMay 22, 2018
Hi there, thanks for your post.
In the stimulus, there is a specific cause (sense of smell) posited for a specific effect (turtles returning to nest).
The question stem asks you to identify the one answer choice that describes what information would be most important to know in evaluating the hypothesis in the stimulus.
Answer choice (B) is irrelevant. Regardless of the sea turtles' migratory range, the hypothesis set forth in the stimulus draws a causal connection between sense of smell and returning to nest. Whether you knew that turtles' migratory range was large or small, that would not help you evaluate the smell-based theory set out in the stimulus.
Hope this helps! Please let us know if you have any additional questions.
