|Question 13Verbal

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The presence of other individuals of the same species has been observed to mitigate stress in highly social mammals. To investigate whether this phenomenon, known as social buffering, also occurs in reptiles, researchers led by Chelsea E. Martin monitored stress responses in wild southern Pacific rattlesnakes (Crotalus helleri) in three experimental treatments: when alone, with a rope, and with a companion C. helleri. The researchers compared the percent change between baseline and peak heart rate in response to a (harmless) disturbance, with higher values indicating higher stress levels.
Which finding, if true, would most directly support the idea that social buffering occurs among C. helleri?
Average peak heart rates were highest among solitary C. helleri, but no differences were observed in average peak heart rates between C. helleri with a companion and C. helleri with a rope.
A
C. helleri with a companion displayed a lower average baseline heart rate and lower average peak heart rate than did solitary C. helleri or C. helleri with a rope.
B
The average percent change in heart rate was lower among C. helleri with a companion than among solitary C. helleri and C. helleri with a rope.
C
Solitary C. helleri had higher average baseline heart rates than did C. helleri in the other treatments, but the average percent change in heart rate was smaller among solitary C. helleri than among C. helleri with a companion.
D