Answer:
See explanation
Step-by-step explanation:
The laboratory provides a controlled environment for scientific studies. In the field, it is more difficult to control extraneous variables. Extraneous variables are other variables which are not the independent variable but could inadvertently affect the dependent variable.
Extraneous variables are better controlled in the secluded environment of a laboratory better than they could be controlled in the field. This makes it more difficult to have control variables in the field than it is to have them in the laboratory. Recall that control variables are variables that must remain unchanged throughout the study.