Answer:
Experimental
Step-by-step explanation:
Experimental study: In research methods, an experimental study is described as a study in which the different conditions are considered to be under the direct influence or control of the researcher or the investigator. An experimental study is being employed or conducted in order to test the efficacy of a particular therapeutic or preventive measure. It can provide the investigator or the researcher with the 'strongest evidence' related to the occurrence of a "cause and effect relationship".
In the question above, the given statement signifies the experimental study.