Answer:
Marcello was surprised to learn that the experimental method is the best way to uncover cause-and-effect relationships because an experiment is a procedure carried out to support, refute or validate a hypothesis or theory. Experiments provide insight into cause-and-effect by demonstrating what outcome occurs when a particular factor is manipulated. Experiments vary greatly in goal and scale, but always rely on repeatable procedure and logical analysis of the results.
Step-by-step explanation:
Generally, in experimental method, one or more variables are manipulated to determine their effect on a dependent variable. The experimental method is a systematic and scientific approach in research in which the researcher manipulates one or more variables and controls and measures any change in other variables.
Moreover, experimental designs often make use of controls that provide a measure of variability within a system and a check for sources of errors.