Self-study
Researchers have found that some unprotected areas outside of a national park that was designed to protect birds have substantially higher numbers of certain bird species than comparable areas inside the park.
"Surprising" Phenomenon
Some unprotected areas outside of a bird conservation park have substantially higher populations of certain bird species than does the park.
Objective
The correct answer will be a hypothesis that explains why certain species are more prevalent outside the park than inside the park. The explanation must account for a feature of the species themselves, or something about the park that makes it less hospitable to these species than one would assume. We need a distinction that makes it more likely for certain bird species to live outside the park.
23.
Which one of the following, ██ █████ ████ █████ ██ ███████ ███ ████████████ ████████
a
Moose are much ████ █████████ ██████ ███ █████ █████ ███████ ██ ███████████ ████ ███████ ███ █████ ███ █████ ███ ████ ██ ███ ████ ████ ███ █████ ████ ██ ████████
The park has a moose problem, which reduces food available for the birds. This isn’t true of areas outside the park, hence why certain bird species make their homes there. This explains what is more attractive about the outside areas.
b
The researchers also █████ ████ ████ ███████████ █████ ███████ ██ ███ ████ ████ █████████████ ██████ ███████ ██ ███████ ███████ ███████ ████ ██████████ █████ ██████ ███ █████
Rather than clearing anything up about the birds, now we also have to account for reptiles. We still don't know what, if anything, makes the outside areas better for birds, or if it's related to the reptiles.
c
Researchers tagged a █████ ██████ ██ █████ ██████ ███ █████ █████ ██████ █████ ████ ██ █████ █████ ████ ██████████ ███████ ███ █████
So a few individual birds sometimes travel across the boundaries of the park. Why did these birds leave the park? Is this related to the birds that habitually live in outside areas? We don't know.
d
Both inside the ████ ███ ████ ███████ ██ ███ █████ ███ █████████ █████ ██████████ ███████ ███ █████ █████████ ██████ ████ ███ ████ ███████ ██████ ███
This points to a similarity between the two areas in question. We need a difference that helps explain why some birds prefer not to live in the protected park.
e
The park was ████████ ██ ███████ ██████████ ████ ████████ ███ ████ ██ ███ ████ ███████ ████ ███ ███████ ██ ██████ ███████ ██ ███ ███████████ █████ ███ ████ ███████████
And why don’t these endangered birds live in the park? Like (D), this is missing a comparative aspect between the park and the unprotected areas. We still don't know why birds might prefer the outside areas.