What is an observational​ study?
a. An observational study measures the value of the response variable without attempting to influence the value of either the response or explanatory variables.
b. An observational study is when a researcher assigns individuals to a certain​ group, intentionally changing the value of an explanatory​ variable, and then recording the value of the response variable for each group.
c. An observational study is a list of all individuals in a population along with certain characteristics of each individual. What is a designed​ experiment?
a. A designed experiment measures the value of the response variable without attempting to influence the value of either the response or explanatory variables.
b. A designed experiment is when a researcher assigns individuals to a certain​ group, intentionally changing the value of an explanatory​ variable, and then recording the value of the response variable for each group.
c. A designed experiment is a list of all individuals in a population along with certain characteristics of each individual. Which allows the researcher to claim causation between an explanatory variable and a response​ variable? ▼ allows the researcher to claim causation between an explanatory variable and a response variable?