Nhận biết (M1)

Water flowing around an obstruction creates vortices (patterns of swirls) of varying size; by detecting the vortices, fish can determine the size and position of the obstruction. Testing by Yuzo R. Yanagisuru, Otar Akanyeti, and James C. Liao using models of three head shapes—narrow (low ratio of width to length), intermediate, and wide (high ratio of width to length)—showed that for large vortices, fish with intermediate heads would be better able than narrow-headed fish to distinguish between vortices and general turbulence in the water. A second research team has therefore hypothesized that in low-visibility conditions, intermediate-headed fish will be more likely than narrow-headed fish to detect obstructions that create large vortices.

Which experimental finding, if true, would most directly support the second research team's hypothesis?

• A.

  A study using obstructions that created large vortices in low-visibility conditions found that the narrow-headed lake sturgeon (Acipenser fulvescens) bumped into obstructions more often than the intermediate-headed dusky smooth-hound (Mustelus canis) did.

• B.

  A study using obstructions that created large vortices in low-visibility conditions found that the lake sturgeon (Acipenser fulvescens), which has a relatively narrow head, bumped into more than half of the obstructions.

• C.

  A study using obstructions that created large vortices in low-visibility conditions found that some specimens of the intermediate-headed dusky smooth-hound (Mustelus canis) bumped into the obstructions more often than other specimens of the same fish did.

• D.

  A study using obstructions that created large vortices in low-visibility conditions found that the intermediate-headed dusky smooth-hound (Mustelus canis) avoided more than half of the obstructions.