Sorrow
Certain species of fish swim in large clusters called schools,whose function is not entirely understood.Experiments have shown that individual fish,when removed from a school,demonstrate higher heart rates than those found withing the school.Fish may experience stress at being separated from fellow members of their species,but an alternative explanation is that,for hydrodynamic reasons,swimming alone requires more physical exertion.
Which of the following,if discovered in an experiment,would support one of the two hypotheses and undermine the other?
A. When a school of fish is made to swim in turbulent condition,the heart rate of each individual fish increases.
B. When individual fish are isolated from their school but are permitted to swim in close proximity to others members of their species,their heart rates remain normal.
C. When a school of fish is threatened by a predator,the heart rates of the fish within it will remain steady,while the heart rates of individual fish will increase significantly.
D. When individual fish are removed from a school,they demonstrate higher heart rates than types of fish that do not normally swim in schools.
E. When a school of fish is threatened by a predator,the fish within it will demonstrate higher heart rates than individual fish isolated from their schools.
Source: Gmatprep software
There is one fact and are 2 hypothesis to explain the fact.
Fact/conclusion : Fish has higher heart rate when isolated than when in School
Hypothesis 1: Isolation from their fellow members of the species causes Stress leading to higher heart rate
Hypothesis 2: Isolation demands more physical exertion than when in School.
Let's look at the choices and how to support or refute.
A. When a school of fish is made to swim in turbulent condition,the heart rate of each individual fish increases.
Does not support or refute either hypothesis.B. When individual fish are isolated from their school but are permitted to swim in close proximity to others members of their species,their heart rates remain normal.
Supports Hypothesis 2 and Refutes 1 by stating "other members" instead of "fellow members"C. When a school of fish is threatened by a predator,the heart rates of the fish within it will remain steady,while the heart rates of individual fish will increase significantly.
Reiterates the conclusion,but neither support nor refutes any of the hypothesis.D. When individual fish are removed from a school,they demonstrate higher heart rates than types of fish that do not normally swim in schools.
Reiterates the conclusion,but neither support nor refutes any of the hypothesis.E. When a school of fish is threatened by a predator,the fish within it will demonstrate higher heart rates than individual fish isolated from their schools.
Out of scope