Which research method gives researchers the ability to infer a cause-and-effect relationship

A)  correlational 
B)  experimental 
C)  case history 
D)  empirical

Experimental research involves manipulating an independent variable and observing a dependent variable, allowing researchers to infer causation. Other methods, such as correlational research, can only identify relationships between variables but do not establish causation. Case history and empirical research refer more to the general approach or source of data, rather than the specific method of inferring cause-and-effect relationships.