Question

1. which of the following is an example of a controlled experiment? an experiment where there are many uncontrolled variables. an experiment where there are no variables. an experiment where there is only one variable.

Explanation:

A controlled experiment aims to test the effect of one independent variable by keeping other variables constant (controlled). Let's analyze each option:

• The first option says there are many uncontrolled variables, which goes against the definition of a controlled experiment (as controlled experiments minimize uncontrolled variables).
• The second option says there are no variables, but experiments inherently involve variables (to test cause - effect relationships), so this is incorrect.
• The third option says there is only one variable. In a controlled experiment, we manipulate one independent variable (while controlling others), so having only one variable (the one being tested, with others controlled) fits the concept of a controlled experiment.

Answer:

The correct option is: An experiment where there is only one variable.