Question #6422589Single Choice
Biology
Question
A student wants to test the hypothesis that caffeine boosts the heart rate of daphnia (a small crustacean). She prepares three beakers: Beaker A with a high concentration of caffeine solution, Beaker B with a low concentration of caffeine solution, and Beaker C with plain water. After placing daphnia in each beaker and observing their heart rates, which beaker serves as the control?
Options
A
Beaker A
B
Beaker B
C
Beaker C
D
None of the above, as all are experimental
Answer & Analysis
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