What is the key difference between an experiment and a quasi-experiment?

Question

Quizplus · Accepted Answer

The key difference between an experiment and a quasi-experiment is that quasi-experiments do not include random assignment of participants to groups. This lack of randomization makes it more difficult to establish causal relationships between the independent variable and the dependent variable, but quasi-experiments are often used when it is not possible or ethical to manipulate the independent variable in a true experiment.

What Is the Key Difference Between an Experiment and a Quasi-Experiment