Question

what is the standard for comparison in an experiment where no variables are changed?
constant
control
theory
derived unit

Explanation:

• A constant is a value that does not change during an experiment, but it is not the standard for comparison.
• A control in an experiment is the group where no variables are changed. It serves as the standard for comparison to see the effect of the independent variable on the experimental group.
• A theory is a well - tested explanation for a wide range of observations. It is not related to the standard of comparison in an experiment.
• A derived unit is a unit that is derived from base units in the metric system. It has no relation to the comparison standard in an experiment.

Answer:

Control