It is uncontrolled.
Answer: Option A.
Step-by-step explanation:
An experiment is a technique done to help, disprove, or approve a theory. Investigations give knowledge into circumstances and logical results by showing what result happens when a specific factor is manipulated.
An experiment is a methodology intended to test a theory as a feature of the logical strategy. The two key factors in any examination are the free and ward factors. The free factor is controlled or changed to test its impacts on the needy variable.