Question

A sample of digestive juice was removed from the stomach of a pig. The juice was

placed in a test tube along with some grains of wheat. A second test tube was set up
containing an equal number of wheat grains, with distilled water rather than
digestive juice. The test tubes were kept for 8 hours at 40 degrees C. After 8 hours,
the grains inside the digestive juice had broken into tiny particles. The grains of
wheat, in the water, were wet but otherwise unchanged.
What is the control group?
test tube with wheat and water
test tube with wheat and digestive juice
the same temperature
the presence or absence of digestive juice

Answer 1

The control group is the test tube with wheat and water.

Step-by-step explanation:

This is because the control group is set up to be compared to the outcome of the test subject influenced by the independent variable, which is this case is the digestive juice. The water and wheat shows the true effect of the digestive juice on breaking down part of a pig's diet, which is wheat.